2644363640 has 16 divisors (see below), whose sum is σ = 5949818280. Its totient is φ = 1057745440.

The previous prime is 2644363621. The next prime is 2644363663. The reversal of 2644363640 is 463634462.

It is a junction number, because it is equal to n+sod(n) for n = 2644363594 and 2644363603.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 33054506 + ... + 33054585.

Almost surely, 2^2644363640 is an apocalyptic number.

2644363640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2644363640 is an abundant number, since it is smaller than the sum of its proper divisors (3305454640).

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

2644363640 is a wasteful number, since it uses less digits than its factorization.

2644363640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66109102 (or 66109098 counting only the distinct ones).

The product of its (nonzero) digits is 248832, while the sum is 38.

The square root of 2644363640 is about 51423.3763963433. The cubic root of 2644363640 is about 1382.8457066170.

The spelling of 2644363640 in words is "two billion, six hundred forty-four million, three hundred sixty-three thousand, six hundred forty".