64398921 has 8 divisors (see below), whose sum is σ = 87041760. Its totient is φ = 42344352.

The previous prime is 64398911. The next prime is 64398931. The reversal of 64398921 is 12989346.

It is an interprime number because it is at equal distance from previous prime (64398911) and next prime (64398931).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 64398921 - 2⁹ = 64398409 is a prime.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (64398911) 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, 146811 + ... + 147248.

It is an arithmetic number, because the mean of its divisors is an integer number (10880220).

Almost surely, 2^64398921 is an apocalyptic number.

It is an amenable number.

64398921 is a deficient number, since it is larger than the sum of its proper divisors (22642839).

64398921 is a wasteful number, since it uses less digits than its factorization.

64398921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 294135.

The product of its digits is 93312, while the sum is 42.

The square root of 64398921 is about 8024.8938310734. The cubic root of 64398921 is about 400.8293646140.

The spelling of 64398921 in words is "sixty-four million, three hundred ninety-eight thousand, nine hundred twenty-one".