21137367 has 16 divisors (see below), whose sum is σ = 29980160. Its totient is φ = 13208832.

The previous prime is 21137359. The next prime is 21137371. The reversal of 21137367 is 76373112.

It is not a de Polignac number, because 21137367 - 2³ = 21137359 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21137327) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3618 + ... + 7440.

It is an arithmetic number, because the mean of its divisors is an integer number (1873760).

Almost surely, 2^21137367 is an apocalyptic number.

21137367 is a deficient number, since it is larger than the sum of its proper divisors (8842793).

21137367 is a wasteful number, since it uses less digits than its factorization.

21137367 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3942.

The product of its digits is 5292, while the sum is 30.

The square root of 21137367 is about 4597.5392331116. The cubic root of 21137367 is about 276.4926744274.

The spelling of 21137367 in words is "twenty-one million, one hundred thirty-seven thousand, three hundred sixty-seven".