64693980 has 72 divisors (see below), whose sum is σ = 211341312. Its totient is φ = 15924096.

The previous prime is 64693961. The next prime is 64693997. The reversal of 64693980 is 8939646.

It is a super-2 number, since 2×64693980² = 8370622096480800, which contains 22 as substring.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent 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, 11484 + ... + 16163.

It is an arithmetic number, because the mean of its divisors is an integer number (2935296).

Almost surely, 2^64693980 is an apocalyptic number.

64693980 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

64693980 is an abundant number, since it is smaller than the sum of its proper divisors (146647332).

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

64693980 is a wasteful number, since it uses less digits than its factorization.

64693980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27675 (or 27670 counting only the distinct ones).

The product of its (nonzero) digits is 279936, while the sum is 45.

The square root of 64693980 is about 8043.2568030618. The cubic root of 64693980 is about 401.4405971378.

The spelling of 64693980 in words is "sixty-four million, six hundred ninety-three thousand, nine hundred eighty".