640617910 has 8 divisors (see below), whose sum is σ = 1153112256. Its totient is φ = 256247160.

The previous prime is 640617893. The next prime is 640617911. The reversal of 640617910 is 19716046.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×640617910² = 820782613225536200, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640617911) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32030886 + ... + 32030905.

It is an arithmetic number, because the mean of its divisors is an integer number (144139032).

Almost surely, 2^640617910 is an apocalyptic number.

640617910 is a deficient number, since it is larger than the sum of its proper divisors (512494346).

640617910 is a wasteful number, since it uses less digits than its factorization.

640617910 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64061798.

The product of its (nonzero) digits is 9072, while the sum is 34.

The square root of 640617910 is about 25310.4308537014. The cubic root of 640617910 is about 862.0511298745.

The spelling of 640617910 in words is "six hundred forty million, six hundred seventeen thousand, nine hundred ten".