65643480 has 256 divisors, whose sum is σ = 263808000. Its totient is φ = 14183424.

The previous prime is 65643469. The next prime is 65643481. The reversal of 65643480 is 8434656.

65643480 = T₁₆₉ + T₁₇₀ + ... + T₇₃₅.

65643480 is a `hidden beast` number, since 6 + 5 + 643 + 4 + 8 + 0 = 666.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65643481) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 143412 + ... + 143868.

It is an arithmetic number, because the mean of its divisors is an integer number (1030500).

Almost surely, 2^65643480 is an apocalyptic number.

65643480 is a gapful number since it is divisible by the number (60) 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 65643480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (131904000).

65643480 is an abundant number, since it is smaller than the sum of its proper divisors (198164520).

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

65643480 is a wasteful number, since it uses less digits than its factorization.

65643480 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 503 (or 493 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 36.

The square root of 65643480 is about 8102.0664030851. The cubic root of 65643480 is about 403.3950197450.

It can be divided in two parts, 65 and 643480, that added together give a triangular number (643545 = T₁₁₃₄).

The spelling of 65643480 in words is "sixty-five million, six hundred forty-three thousand, four hundred eighty".