21393962 has 16 divisors (see below), whose sum is σ = 34568160. Its totient is φ = 9897552.

The previous prime is 21393961. The next prime is 21393989. The reversal of 21393962 is 26939312.

It is a super-2 number, since 2×21393962² = 915403220114888, which contains 22 as substring.

It is a Smith number, since the sum of its digits (35) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (21393961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4913 + ... + 8180.

It is an arithmetic number, because the mean of its divisors is an integer number (2160510).

Almost surely, 2^21393962 is an apocalyptic number.

21393962 is a deficient number, since it is larger than the sum of its proper divisors (13174198).

21393962 is a wasteful number, since it uses less digits than its factorization.

21393962 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13157.

The product of its digits is 17496, while the sum is 35.

The square root of 21393962 is about 4625.3607426881. The cubic root of 21393962 is about 277.6069960477.

The spelling of 21393962 in words is "twenty-one million, three hundred ninety-three thousand, nine hundred sixty-two".