21077660 has 24 divisors (see below), whose sum is σ = 46188576. Its totient is φ = 8064320.

The previous prime is 21077659. The next prime is 21077741. The reversal of 21077660 is 6677012.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22451 + ... + 23370.

It is an arithmetic number, because the mean of its divisors is an integer number (1924524).

Almost surely, 2^21077660 is an apocalyptic number.

21077660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21077660 is an abundant number, since it is smaller than the sum of its proper divisors (25110916).

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

21077660 is a wasteful number, since it uses less digits than its factorization.

21077660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45853 (or 45851 counting only the distinct ones).

The product of its (nonzero) digits is 3528, while the sum is 29.

The square root of 21077660 is about 4591.0412762248. The cubic root of 21077660 is about 276.2320914116.

The spelling of 21077660 in words is "twenty-one million, seventy-seven thousand, six hundred sixty".