661042432 has 18 divisors (see below), whose sum is σ = 1319503178. Its totient is φ = 330521088.

The previous prime is 661042423. The next prime is 661042453. The reversal of 661042432 is 234240166.

It can be written as a sum of positive squares in only one way, i.e., 618218496 + 42823936 = 24864^2 + 6544^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 661042432.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1290843 + ... + 1291354.

Almost surely, 2^661042432 is an apocalyptic number.

It is an amenable number.

661042432 is a deficient number, since it is larger than the sum of its proper divisors (658460746).

661042432 is an equidigital number, since it uses as much as digits as its factorization.

661042432 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2582213 (or 2582199 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 28.

The square root of 661042432 is about 25710.7454578820. The cubic root of 661042432 is about 871.1169131303.

Adding to 661042432 its reverse (234240166), we get a palindrome (895282598).

The spelling of 661042432 in words is "six hundred sixty-one million, forty-two thousand, four hundred thirty-two".