640462672 has 10 divisors (see below), whose sum is σ = 1240896458. Its totient is φ = 320231328.

The previous prime is 640462663. The next prime is 640462687. The reversal of 640462672 is 276264046.

It can be written as a sum of positive squares in only one way, i.e., 327031056 + 313431616 = 18084^2 + 17704^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20014443 + ... + 20014474.

Almost surely, 2^640462672 is an apocalyptic number.

It is an amenable number.

640462672 is a deficient number, since it is larger than the sum of its proper divisors (600433786).

640462672 is a wasteful number, since it uses less digits than its factorization.

640462672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40028925 (or 40028919 counting only the distinct ones).

The product of its (nonzero) digits is 96768, while the sum is 37.

The square root of 640462672 is about 25307.3639875827. The cubic root of 640462672 is about 861.9814919503.

The spelling of 640462672 in words is "six hundred forty million, four hundred sixty-two thousand, six hundred seventy-two".