640772160 has 448 divisors, whose sum is σ = 2528133120. Its totient is φ = 134184960.

The previous prime is 640772147. The next prime is 640772161. The reversal of 640772160 is 61277046.

640772160 = T₄₇₅ + T₄₇₆ + ... + T₁₅₈₀.

It is a tau number, because it is divible by the number of its divisors (448).

It is a super-2 number, since 2×640772160² = 821177922062131200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (640772161) 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, 8111001 + ... + 8111079.

Almost surely, 2^640772160 is an apocalyptic number.

640772160 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 640772160, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1264066560).

640772160 is an abundant number, since it is smaller than the sum of its proper divisors (1887360960).

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

640772160 is a wasteful number, since it uses less digits than its factorization.

640772160 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 194 (or 184 counting only the distinct ones).

The product of its (nonzero) digits is 14112, while the sum is 33.

The square root of 640772160 is about 25313.4778329648. The cubic root of 640772160 is about 862.1203134516.

The spelling of 640772160 in words is "six hundred forty million, seven hundred seventy-two thousand, one hundred sixty".