64185491 has 16 divisors (see below), whose sum is σ = 68257728. Its totient is φ = 60278400.

The previous prime is 64185461. The next prime is 64185509. The reversal of 64185491 is 19458146.

It is a cyclic number.

It is not a de Polignac number, because 64185491 - 2⁶ = 64185427 is a prime.

It is a super-2 number, since 2×64185491² = 8239554509822162, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (64185461) 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, 139001 + ... + 139461.

It is an arithmetic number, because the mean of its divisors is an integer number (4266108).

Almost surely, 2^64185491 is an apocalyptic number.

64185491 is a deficient number, since it is larger than the sum of its proper divisors (4072237).

64185491 is a wasteful number, since it uses less digits than its factorization.

64185491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 622.

The product of its digits is 34560, while the sum is 38.

The square root of 64185491 is about 8011.5847995262. The cubic root of 64185491 is about 400.3860668444.

The spelling of 64185491 in words is "sixty-four million, one hundred eighty-five thousand, four hundred ninety-one".