21677420 has 12 divisors (see below), whose sum is σ = 45522624. Its totient is φ = 8670960.

The previous prime is 21677407. The next prime is 21677443. The reversal of 21677420 is 2477612.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 541916 + ... + 541955.

It is an arithmetic number, because the mean of its divisors is an integer number (3793552).

Almost surely, 2^21677420 is an apocalyptic number.

21677420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21677420 is an abundant number, since it is smaller than the sum of its proper divisors (23845204).

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

21677420 is a wasteful number, since it uses less digits than its factorization.

21677420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1083880 (or 1083878 counting only the distinct ones).

The product of its (nonzero) digits is 4704, while the sum is 29.

The square root of 21677420 is about 4655.9016312633. The cubic root of 21677420 is about 278.8276664276.

The spelling of 21677420 in words is "twenty-one million, six hundred seventy-seven thousand, four hundred twenty".