21522607 has 2 divisors, whose sum is σ = 21522608. Its totient is φ = 21522606.

The previous prime is 21522601. The next prime is 21522617. The reversal of 21522607 is 70622512.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21522607 is a prime.

It is a super-2 number, since 2×21522607² = 926445224152898, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21522601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10761303 + 10761304.

It is an arithmetic number, because the mean of its divisors is an integer number (10761304).

Almost surely, 2^21522607 is an apocalyptic number.

21522607 is a deficient number, since it is larger than the sum of its proper divisors (1).

21522607 is an equidigital number, since it uses as much as digits as its factorization.

21522607 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1680, while the sum is 25.

The square root of 21522607 is about 4639.2463827652. The cubic root of 21522607 is about 278.1623148520.

It can be divided in two parts, 215 and 22607, that added together give a palindrome (22822).

The spelling of 21522607 in words is "twenty-one million, five hundred twenty-two thousand, six hundred seven".