21268968 has 32 divisors (see below), whose sum is σ = 60768960. Its totient is φ = 6076800.

The previous prime is 21268967. The next prime is 21268991. The reversal of 21268968 is 86986212.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a zygodrome in base 11.

It is not an unprimeable number, because it can be changed into a prime (21268967) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 63133 + ... + 63468.

It is an arithmetic number, because the mean of its divisors is an integer number (1899030).

Almost surely, 2^21268968 is an apocalyptic number.

21268968 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

21268968 is an abundant number, since it is smaller than the sum of its proper divisors (39499992).

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

21268968 is a wasteful number, since it uses less digits than its factorization.

21268968 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126617 (or 126613 counting only the distinct ones).

The product of its digits is 82944, while the sum is 42.

The square root of 21268968 is about 4611.8291382054. The cubic root of 21268968 is about 277.0653010646.

The spelling of 21268968 in words is "twenty-one million, two hundred sixty-eight thousand, nine hundred sixty-eight".