431553661 has 16 divisors (see below), whose sum is σ = 538697088. Its totient is φ = 335865600.

The previous prime is 431553649. The next prime is 431553673. The reversal of 431553661 is 166355134.

It is an interprime number because it is at equal distance from previous prime (431553649) and next prime (431553673).

It is a de Polignac number, because none of the positive numbers 2^k-431553661 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 (431553961) 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 in 15 ways as a sum of consecutive naturals, for example, 70441 + ... + 76321.

It is an arithmetic number, because the mean of its divisors is an integer number (33668568).

Almost surely, 2^431553661 is an apocalyptic number.

It is an amenable number.

431553661 is a deficient number, since it is larger than the sum of its proper divisors (107143427).

431553661 is a wasteful number, since it uses less digits than its factorization.

431553661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6852.

The product of its digits is 32400, while the sum is 34.

The square root of 431553661 is about 20773.8696684080. The cubic root of 431553661 is about 755.6921921197.

The spelling of 431553661 in words is "four hundred thirty-one million, five hundred fifty-three thousand, six hundred sixty-one".