64721194 has 4 divisors (see below), whose sum is σ = 97081794. Its totient is φ = 32360596.

The previous prime is 64721191. The next prime is 64721207. The reversal of 64721194 is 49112746.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 49112746 = 2 ⋅24556373.

It can be written as a sum of positive squares in only one way, i.e., 51652969 + 13068225 = 7187^2 + 3615^2 .

It is not an unprimeable number, because it can be changed into a prime (64721191) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16180297 + ... + 16180300.

Almost surely, 2^64721194 is an apocalyptic number.

64721194 is a deficient number, since it is larger than the sum of its proper divisors (32360600).

64721194 is a wasteful number, since it uses less digits than its factorization.

64721194 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32360599.

The product of its digits is 12096, while the sum is 34.

The square root of 64721194 is about 8044.9483528485. The cubic root of 64721194 is about 401.4968788965.

The spelling of 64721194 in words is "sixty-four million, seven hundred twenty-one thousand, one hundred ninety-four".