21478700 has 18 divisors (see below), whose sum is σ = 46608996. Its totient is φ = 8591440.

The previous prime is 21478679. The next prime is 21478729. The reversal of 21478700 is 787412.

It is a super-2 number, since 2×21478700² = 922669107380000, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 107294 + ... + 107493.

Almost surely, 2^21478700 is an apocalyptic number.

21478700 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21478700 is an abundant number, since it is smaller than the sum of its proper divisors (25130296).

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

21478700 is a wasteful number, since it uses less digits than its factorization.

21478700 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 214801 (or 214794 counting only the distinct ones).

The product of its (nonzero) digits is 3136, while the sum is 29.

The square root of 21478700 is about 4634.5118405286. The cubic root of 21478700 is about 277.9730319060.

The spelling of 21478700 in words is "twenty-one million, four hundred seventy-eight thousand, seven hundred".