82415621 has 2 divisors, whose sum is σ = 82415622. Its totient is φ = 82415620.

The previous prime is 82415591. The next prime is 82415629. The reversal of 82415621 is 12651428.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 75498721 + 6916900 = 8689^2 + 2630^2 .

It is a cyclic number.

It is not a de Polignac number, because 82415621 - 2²⁶ = 15306757 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (82415629) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41207810 + 41207811.

It is an arithmetic number, because the mean of its divisors is an integer number (41207811).

Almost surely, 2^82415621 is an apocalyptic number.

It is an amenable number.

82415621 is a deficient number, since it is larger than the sum of its proper divisors (1).

82415621 is an equidigital number, since it uses as much as digits as its factorization.

82415621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3840, while the sum is 29.

The square root of 82415621 is about 9078.3049629322. The cubic root of 82415621 is about 435.1809191512.

The spelling of 82415621 in words is "eighty-two million, four hundred fifteen thousand, six hundred twenty-one".