21367457 has 4 divisors (see below), whose sum is σ = 22492080. Its totient is φ = 20242836.

The previous prime is 21367433. The next prime is 21367481. The reversal of 21367457 is 75476312.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (21367433) and next prime (21367481).

It is a cyclic number.

It is not a de Polignac number, because 21367457 - 2⁶ = 21367393 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21307457) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 562283 + ... + 562320.

It is an arithmetic number, because the mean of its divisors is an integer number (5623020).

Almost surely, 2^21367457 is an apocalyptic number.

It is an amenable number.

21367457 is a deficient number, since it is larger than the sum of its proper divisors (1124623).

21367457 is a wasteful number, since it uses less digits than its factorization.

21367457 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1124622.

The product of its digits is 35280, while the sum is 35.

The square root of 21367457 is about 4622.4946727930. The cubic root of 21367457 is about 277.4923061471.

The spelling of 21367457 in words is "twenty-one million, three hundred sixty-seven thousand, four hundred fifty-seven".