647640276 has 24 divisors (see below), whose sum is σ = 1517652864. Its totient is φ = 214952640.

The previous prime is 647640247. The next prime is 647640281. The reversal of 647640276 is 672046746.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 113020 + ... + 118611.

It is an arithmetic number, because the mean of its divisors is an integer number (63235536).

Almost surely, 2^647640276 is an apocalyptic number.

It is an amenable number.

647640276 is an abundant number, since it is smaller than the sum of its proper divisors (870012588).

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

647640276 is a wasteful number, since it uses less digits than its factorization.

647640276 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 231871 (or 231869 counting only the distinct ones).

The product of its (nonzero) digits is 338688, while the sum is 42.

The square root of 647640276 is about 25448.7774951961. Note that the first 3 decimals coincide. The cubic root of 647640276 is about 865.1895854509.

The spelling of 647640276 in words is "six hundred forty-seven million, six hundred forty thousand, two hundred seventy-six".