2643656400 has 1080 divisors, whose sum is σ = 12556349120. Its totient is φ = 517017600.

The previous prime is 2643656381. The next prime is 2643656419. The reversal of 2643656400 is 46563462.

2643656400 = T₄₉₆ + T₄₉₇ + ... + T₂₅₁₈.

2643656400 is a `hidden beast` number, since 2 + 6 + 4 + 3 + 6 + 5 + 640 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (2643656381) and next prime (2643656419).

It is a tau number, because it is divible by the number of its divisors (1080).

It is a super-2 number, since 2×2643656400² = 13977838322521920000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 215 ways as a sum of consecutive naturals, for example, 155509192 + ... + 155509208.

Almost surely, 2^2643656400 is an apocalyptic number.

2643656400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2643656400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (6278174560).

2643656400 is an abundant number, since it is smaller than the sum of its proper divisors (9912692720).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2643656400 is a wasteful number, since it uses less digits than its factorization.

2643656400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90 (or 45 counting only the distinct ones).

The product of its (nonzero) digits is 103680, while the sum is 36.

The square root of 2643656400 is about 51416.4992974045. The cubic root of 2643656400 is about 1382.7224140681.

The spelling of 2643656400 in words is "two billion, six hundred forty-three million, six hundred fifty-six thousand, four hundred".