6475631621 has 2 divisors, whose sum is σ = 6475631622. Its totient is φ = 6475631620.

The previous prime is 6475631611. The next prime is 6475631629. The reversal of 6475631621 is 1261365746.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3774750721 + 2700880900 = 61439^2 + 51970^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6475631621 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6475631629) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3237815810 + 3237815811.

It is an arithmetic number, because the mean of its divisors is an integer number (3237815811).

Almost surely, 2^6475631621 is an apocalyptic number.

It is an amenable number.

6475631621 is a deficient number, since it is larger than the sum of its proper divisors (1).

6475631621 is an equidigital number, since it uses as much as digits as its factorization.

6475631621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 181440, while the sum is 41.

The square root of 6475631621 is about 80471.3093033784. The cubic root of 6475631621 is about 1863.9204720755.

The spelling of 6475631621 in words is "six billion, four hundred seventy-five million, six hundred thirty-one thousand, six hundred twenty-one".