64420690 has 16 divisors (see below), whose sum is σ = 116107992. Its totient is φ = 25734784.

The previous prime is 64420679. The next prime is 64420703. The reversal of 64420690 is 9602446.

It can be written as a sum of positive squares in 4 ways, for example, as 64208169 + 212521 = 8013^2 + 461^2 .

It is a super-2 number, since 2×64420690² = 8300050600152200, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4812 + ... + 12328.

Almost surely, 2^64420690 is an apocalyptic number.

64420690 is a deficient number, since it is larger than the sum of its proper divisors (51687302).

64420690 is a wasteful number, since it uses less digits than its factorization.

64420690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8381.

The product of its (nonzero) digits is 10368, while the sum is 31.

The square root of 64420690 is about 8026.2500584021. The cubic root of 64420690 is about 400.8745241255.

The spelling of 64420690 in words is "sixty-four million, four hundred twenty thousand, six hundred ninety".