628815631 has 2 divisors, whose sum is σ = 628815632. Its totient is φ = 628815630.

The previous prime is 628815599. The next prime is 628815673. The reversal of 628815631 is 136518826.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 628815631 - 2⁵ = 628815599 is a prime.

It is a super-2 number, since 2×628815631² = 790818195579856322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (628855631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 314407815 + 314407816.

It is an arithmetic number, because the mean of its divisors is an integer number (314407816).

Almost surely, 2^628815631 is an apocalyptic number.

628815631 is a deficient number, since it is larger than the sum of its proper divisors (1).

628815631 is an equidigital number, since it uses as much as digits as its factorization.

628815631 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 69120, while the sum is 40.

The square root of 628815631 is about 25076.1965018621. The cubic root of 628815631 is about 856.7243478516.

The spelling of 628815631 in words is "six hundred twenty-eight million, eight hundred fifteen thousand, six hundred thirty-one".