772621921 has 2 divisors, whose sum is σ = 772621922. Its totient is φ = 772621920.

The previous prime is 772621919. The next prime is 772621937. The reversal of 772621921 is 129126277.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 770839696 + 1782225 = 27764^2 + 1335^2 .

It is a cyclic number.

It is not a de Polignac number, because 772621921 - 2¹ = 772621919 is a prime.

Together with 772621919, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (772621981) 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, 386310960 + 386310961.

It is an arithmetic number, because the mean of its divisors is an integer number (386310961).

Almost surely, 2^772621921 is an apocalyptic number.

It is an amenable number.

772621921 is a deficient number, since it is larger than the sum of its proper divisors (1).

772621921 is an equidigital number, since it uses as much as digits as its factorization.

772621921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 21168, while the sum is 37.

The square root of 772621921 is about 27796.0774390920. The cubic root of 772621921 is about 917.6047970341.

The spelling of 772621921 in words is "seven hundred seventy-two million, six hundred twenty-one thousand, nine hundred twenty-one".