731222621 has 2 divisors, whose sum is σ = 731222622. Its totient is φ = 731222620.

The previous prime is 731222603. The next prime is 731222623. The reversal of 731222621 is 126222137.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 639331225 + 91891396 = 25285^2 + 9586^2 .

It is a cyclic number.

It is not a de Polignac number, because 731222621 - 2²⁶ = 664113757 is a prime.

Together with 731222623, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (731222623) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 365611310 + 365611311.

It is an arithmetic number, because the mean of its divisors is an integer number (365611311).

Almost surely, 2^731222621 is an apocalyptic number.

It is an amenable number.

731222621 is a deficient number, since it is larger than the sum of its proper divisors (1).

731222621 is an equidigital number, since it uses as much as digits as its factorization.

731222621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2016, while the sum is 26.

The square root of 731222621 is about 27041.1283233522. The cubic root of 731222621 is about 900.9137308626.

Adding to 731222621 its reverse (126222137), we get a palindrome (857444758).

The spelling of 731222621 in words is "seven hundred thirty-one million, two hundred twenty-two thousand, six hundred twenty-one".