64821996 has 72 divisors (see below), whose sum is σ = 174436080. Its totient is φ = 20238336.

The previous prime is 64821971. The next prime is 64822007. The reversal of 64821996 is 69912846.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 65860 + ... + 66836.

Almost surely, 2^64821996 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 64821996, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (87218040).

64821996 is an abundant number, since it is smaller than the sum of its proper divisors (109614084).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

64821996 is a wasteful number, since it uses less digits than its factorization.

64821996 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1103 (or 1098 counting only the distinct ones).

The product of its digits is 186624, while the sum is 45.

The square root of 64821996 is about 8051.2108406127. The cubic root of 64821996 is about 401.7052119672.

The spelling of 64821996 in words is "sixty-four million, eight hundred twenty-one thousand, nine hundred ninety-six".