645087276 has 72 divisors (see below), whose sum is σ = 1693574064. Its totient is φ = 206876160.

The previous prime is 645087269. The next prime is 645087307. The reversal of 645087276 is 672780546.

645087276 is a `hidden beast` number, since 6 + 4 + 508 + 72 + 76 = 666.

It is a super-2 number, since 2×645087276² = 832275187314200352, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 104755 + ... + 110741.

It is an arithmetic number, because the mean of its divisors is an integer number (23521862).

Almost surely, 2^645087276 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 645087276, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (846787032).

645087276 is an abundant number, since it is smaller than the sum of its proper divisors (1048486788).

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

645087276 is a wasteful number, since it uses less digits than its factorization.

645087276 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6111 (or 6106 counting only the distinct ones).

The product of its (nonzero) digits is 564480, while the sum is 45.

The square root of 645087276 is about 25398.5683848519. The cubic root of 645087276 is about 864.0512283154.

The spelling of 645087276 in words is "six hundred forty-five million, eighty-seven thousand, two hundred seventy-six".