21348738 has 32 divisors (see below), whose sum is σ = 49507200. Its totient is φ = 6806448.

The previous prime is 21348731. The next prime is 21348749. The reversal of 21348738 is 83784312.

It is a super-2 number, since 2×21348738² = 911537228385288, which contains 22 as substring.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (21348731) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7353 + ... + 9836.

It is an arithmetic number, because the mean of its divisors is an integer number (1547100).

Almost surely, 2^21348738 is an apocalyptic number.

21348738 is an abundant number, since it is smaller than the sum of its proper divisors (28158462).

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

21348738 is a wasteful number, since it uses less digits than its factorization.

21348738 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17223 (or 17217 counting only the distinct ones).

The product of its digits is 32256, while the sum is 36.

The square root of 21348738 is about 4620.4694566678. The cubic root of 21348738 is about 277.4112499243.

The spelling of 21348738 in words is "twenty-one million, three hundred forty-eight thousand, seven hundred thirty-eight".