64921970 has 16 divisors (see below), whose sum is σ = 117108288. Its totient is φ = 25913520.

The previous prime is 64921943. The next prime is 64921973. The reversal of 64921970 is 7912946.

It is not an unprimeable number, because it can be changed into a prime (64921973) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1796 + ... + 11535.

It is an arithmetic number, because the mean of its divisors is an integer number (7319268).

Almost surely, 2^64921970 is an apocalyptic number.

64921970 is a deficient number, since it is larger than the sum of its proper divisors (52186318).

64921970 is a wasteful number, since it uses less digits than its factorization.

64921970 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13825.

The product of its (nonzero) digits is 27216, while the sum is 38.

The square root of 64921970 is about 8057.4170799332. The cubic root of 64921970 is about 401.9116205472.

The spelling of 64921970 in words is "sixty-four million, nine hundred twenty-one thousand, nine hundred seventy".