20615629 has 2 divisors, whose sum is σ = 20615630. Its totient is φ = 20615628.

The previous prime is 20615599. The next prime is 20615653. The reversal of 20615629 is 92651602.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16793604 + 3822025 = 4098^2 + 1955^2 .

It is a cyclic number.

It is not a de Polignac number, because 20615629 - 2⁵ = 20615597 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20615629.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20615669) 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 as a sum of consecutive naturals, namely, 10307814 + 10307815.

It is an arithmetic number, because the mean of its divisors is an integer number (10307815).

Almost surely, 2^20615629 is an apocalyptic number.

It is an amenable number.

20615629 is a deficient number, since it is larger than the sum of its proper divisors (1).

20615629 is an equidigital number, since it uses as much as digits as its factorization.

20615629 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6480, while the sum is 31.

The square root of 20615629 is about 4540.4437007852. The cubic root of 20615629 is about 274.1987874936.

The spelling of 20615629 in words is "twenty million, six hundred fifteen thousand, six hundred twenty-nine".