631011621 has 4 divisors (see below), whose sum is σ = 841348832. Its totient is φ = 420674412.

The previous prime is 631011581. The next prime is 631011629. The reversal of 631011621 is 126110136.

631011621 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 631011621 - 2²¹ = 628914469 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (631011629) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 105168601 + ... + 105168606.

It is an arithmetic number, because the mean of its divisors is an integer number (210337208).

Almost surely, 2^631011621 is an apocalyptic number.

It is an amenable number.

631011621 is a deficient number, since it is larger than the sum of its proper divisors (210337211).

631011621 is a wasteful number, since it uses less digits than its factorization.

631011621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 210337210.

The product of its (nonzero) digits is 216, while the sum is 21.

The square root of 631011621 is about 25119.9446854487. The cubic root of 631011621 is about 857.7204915971.

Adding to 631011621 its reverse (126110136), we get a palindrome (757121757).

The spelling of 631011621 in words is "six hundred thirty-one million, eleven thousand, six hundred twenty-one".