642647730 has 32 divisors (see below), whose sum is σ = 1551602304. Its totient is φ = 170345216.

The previous prime is 642647723. The next prime is 642647777. The reversal of 642647730 is 37746246.

It is a super-2 number, since 2×642647730² = 825992209748305800, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 59127 + ... + 69146.

It is an arithmetic number, because the mean of its divisors is an integer number (48487572).

Almost surely, 2^642647730 is an apocalyptic number.

642647730 is an abundant number, since it is smaller than the sum of its proper divisors (908954574).

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

642647730 is a wasteful number, since it uses less digits than its factorization.

642647730 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128450.

The product of its (nonzero) digits is 169344, while the sum is 39.

The square root of 642647730 is about 25350.4976282518. The cubic root of 642647730 is about 862.9606495397.

The spelling of 642647730 in words is "six hundred forty-two million, six hundred forty-seven thousand, seven hundred thirty".