21072629 has 2 divisors, whose sum is σ = 21072630. Its totient is φ = 21072628.

The previous prime is 21072613. The next prime is 21072659. The reversal of 21072629 is 92627012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19802500 + 1270129 = 4450^2 + 1127^2 .

It is a cyclic number.

It is not a de Polignac number, because 21072629 - 2⁴ = 21072613 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21072659) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10536314 + 10536315.

It is an arithmetic number, because the mean of its divisors is an integer number (10536315).

Almost surely, 2^21072629 is an apocalyptic number.

It is an amenable number.

21072629 is a deficient number, since it is larger than the sum of its proper divisors (1).

21072629 is an equidigital number, since it uses as much as digits as its factorization.

21072629 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3024, while the sum is 29.

The square root of 21072629 is about 4590.4933286086. The cubic root of 21072629 is about 276.2101118332.

The spelling of 21072629 in words is "twenty-one million, seventy-two thousand, six hundred twenty-nine".