82721413 has 2 divisors, whose sum is σ = 82721414. Its totient is φ = 82721412.

The previous prime is 82721411. The next prime is 82721437. The reversal of 82721413 is 31412728.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 61496964 + 21224449 = 7842^2 + 4607^2 .

It is a cyclic number.

It is not a de Polignac number, because 82721413 - 2¹ = 82721411 is a prime.

Together with 82721411, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (82721411) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41360706 + 41360707.

It is an arithmetic number, because the mean of its divisors is an integer number (41360707).

Almost surely, 2^82721413 is an apocalyptic number.

It is an amenable number.

82721413 is a deficient number, since it is larger than the sum of its proper divisors (1).

82721413 is an equidigital number, since it uses as much as digits as its factorization.

82721413 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2688, while the sum is 28.

The square root of 82721413 is about 9095.1312799761. The cubic root of 82721413 is about 435.7184814687.

The spelling of 82721413 in words is "eighty-two million, seven hundred twenty-one thousand, four hundred thirteen".