21403368 has 48 divisors (see below), whose sum is σ = 66250080. Its totient is φ = 6115104.

The previous prime is 21403337. The next prime is 21403399. The reversal of 21403368 is 86330412.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21403337) and next prime (21403399).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 20730 + ... + 21737.

It is an arithmetic number, because the mean of its divisors is an integer number (1380210).

Almost surely, 2^21403368 is an apocalyptic number.

21403368 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

21403368 is an abundant number, since it is smaller than the sum of its proper divisors (44846712).

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

21403368 is a wasteful number, since it uses less digits than its factorization.

21403368 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42486 (or 42479 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The square root of 21403368 is about 4626.3774165107. The cubic root of 21403368 is about 277.6476740175.

The spelling of 21403368 in words is "twenty-one million, four hundred three thousand, three hundred sixty-eight".