640798674 has 64 divisors (see below), whose sum is σ = 1403136000. Its totient is φ = 194322240.

The previous prime is 640798667. The next prime is 640798681. The reversal of 640798674 is 476897046.

It is an interprime number because it is at equal distance from previous prime (640798667) and next prime (640798681).

It is a super-4 number, since 4×640798674⁴ (a number of 36 digits) contains 4444 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 789729 + ... + 790539.

It is an arithmetic number, because the mean of its divisors is an integer number (21924000).

Almost surely, 2^640798674 is an apocalyptic number.

640798674 is an abundant number, since it is smaller than the sum of its proper divisors (762337326).

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

640798674 is a wasteful number, since it uses less digits than its factorization.

640798674 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1103.

The product of its (nonzero) digits is 2032128, while the sum is 51.

The square root of 640798674 is about 25314.0015406494. The cubic root of 640798674 is about 862.1322042838.

The spelling of 640798674 in words is "six hundred forty million, seven hundred ninety-eight thousand, six hundred seventy-four".