64219906 has 4 divisors (see below), whose sum is σ = 96329862. Its totient is φ = 32109952.

The previous prime is 64219877. The next prime is 64219919. The reversal of 64219906 is 60991246.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 63345681 + 874225 = 7959^2 + 935^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16054975 + ... + 16054978.

Almost surely, 2^64219906 is an apocalyptic number.

64219906 is a deficient number, since it is larger than the sum of its proper divisors (32109956).

64219906 is a wasteful number, since it uses less digits than its factorization.

64219906 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32109955.

The product of its (nonzero) digits is 23328, while the sum is 37.

The square root of 64219906 is about 8013.7323389292. The cubic root of 64219906 is about 400.4576137744.

The spelling of 64219906 in words is "sixty-four million, two hundred nineteen thousand, nine hundred six".