640154308 has 24 divisors (see below), whose sum is σ = 1230505920. Its totient is φ = 290046240.

The previous prime is 640154269. The next prime is 640154321. The reversal of 640154308 is 803451046.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 640154308.

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, 181363 + ... + 184858.

It is an arithmetic number, because the mean of its divisors is an integer number (51271080).

Almost surely, 2^640154308 is an apocalyptic number.

It is an amenable number.

640154308 is a deficient number, since it is larger than the sum of its proper divisors (590351612).

640154308 is a wasteful number, since it uses less digits than its factorization.

640154308 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 366267 (or 366265 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 31.

The square root of 640154308 is about 25301.2708771714. The cubic root of 640154308 is about 861.8431301364.

The spelling of 640154308 in words is "six hundred forty million, one hundred fifty-four thousand, three hundred eight".