21457700 has 36 divisors (see below), whose sum is σ = 50798832. Its totient is φ = 7802400.

The previous prime is 21457697. The next prime is 21457703. The reversal of 21457700 is 775412.

It is an interprime number because it is at equal distance from previous prime (21457697) and next prime (21457703).

It is a self number, because there is not a number n which added to its sum of digits gives 21457700.

It is not an unprimeable number, because it can be changed into a prime (21457703) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 8654 + ... + 10853.

Almost surely, 2^21457700 is an apocalyptic number.

21457700 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21457700 is an abundant number, since it is smaller than the sum of its proper divisors (29341132).

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

21457700 is a wasteful number, since it uses less digits than its factorization.

21457700 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19532 (or 19525 counting only the distinct ones).

The product of its (nonzero) digits is 1960, while the sum is 26.

The square root of 21457700 is about 4632.2456756955. The cubic root of 21457700 is about 277.8824097680.

The spelling of 21457700 in words is "twenty-one million, four hundred fifty-seven thousand, seven hundred".