64691943 has 16 divisors (see below), whose sum is σ = 88515840. Its totient is φ = 42012864.

The previous prime is 64691927. The next prime is 64691969. The reversal of 64691943 is 34919646.

It is not a de Polignac number, because 64691943 - 2⁴ = 64691927 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 64691895 and 64691904.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64691983) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16398 + ... + 19956.

It is an arithmetic number, because the mean of its divisors is an integer number (5532240).

Almost surely, 2^64691943 is an apocalyptic number.

64691943 is a deficient number, since it is larger than the sum of its proper divisors (23823897).

64691943 is a wasteful number, since it uses less digits than its factorization.

64691943 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3718.

The product of its digits is 139968, while the sum is 42.

The square root of 64691943 is about 8043.1301742543. The cubic root of 64691943 is about 401.4363837469.

The spelling of 64691943 in words is "sixty-four million, six hundred ninety-one thousand, nine hundred forty-three".