64123491 has 16 divisors (see below), whose sum is σ = 86688000. Its totient is φ = 42158688.

The previous prime is 64123487. The next prime is 64123513. The reversal of 64123491 is 19432146.

It is not a de Polignac number, because 64123491 - 2² = 64123487 is a prime.

It is a super-2 number, since 2×64123491² = 8223644196054162, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (64123421) 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, 74220 + ... + 75078.

It is an arithmetic number, because the mean of its divisors is an integer number (5418000).

Almost surely, 2^64123491 is an apocalyptic number.

64123491 is a deficient number, since it is larger than the sum of its proper divisors (22564509).

64123491 is a wasteful number, since it uses less digits than its factorization.

64123491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1178.

The product of its digits is 5184, while the sum is 30.

The square root of 64123491 is about 8007.7144679365. The cubic root of 64123491 is about 400.2571076204.

The spelling of 64123491 in words is "sixty-four million, one hundred twenty-three thousand, four hundred ninety-one".