624651421 has 2 divisors, whose sum is σ = 624651422. Its totient is φ = 624651420.

The previous prime is 624651409. The next prime is 624651449. The reversal of 624651421 is 124156426.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 624500100 + 151321 = 24990^2 + 389^2 .

It is a cyclic number.

It is not a de Polignac number, because 624651421 - 2⁵ = 624651389 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (624651121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 312325710 + 312325711.

It is an arithmetic number, because the mean of its divisors is an integer number (312325711).

Almost surely, 2^624651421 is an apocalyptic number.

It is an amenable number.

624651421 is a deficient number, since it is larger than the sum of its proper divisors (1).

624651421 is an equidigital number, since it uses as much as digits as its factorization.

624651421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 11520, while the sum is 31.

The square root of 624651421 is about 24993.0274476703. The cubic root of 624651421 is about 854.8289939909.

The spelling of 624651421 in words is "six hundred twenty-four million, six hundred fifty-one thousand, four hundred twenty-one".