661725442 has 32 divisors (see below), whose sum is σ = 1239874560. Its totient is φ = 258301440.

The previous prime is 661725439. The next prime is 661725487. The reversal of 661725442 is 244527166.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 37467 + ... + 52222.

It is an arithmetic number, because the mean of its divisors is an integer number (38746080).

Almost surely, 2^661725442 is an apocalyptic number.

661725442 is a gapful number since it is divisible by the number (62) formed by its first and last digit.

661725442 is a deficient number, since it is larger than the sum of its proper divisors (578149118).

661725442 is a wasteful number, since it uses less digits than its factorization.

661725442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 89746.

The product of its digits is 80640, while the sum is 37.

The square root of 661725442 is about 25724.0246073588. The cubic root of 661725442 is about 871.4168317304.

The spelling of 661725442 in words is "six hundred sixty-one million, seven hundred twenty-five thousand, four hundred forty-two".