661457757 has 16 divisors (see below), whose sum is σ = 921927680. Its totient is φ = 421340400.

The previous prime is 661457707. The next prime is 661457761. The reversal of 661457757 is 757754166.

It is not a de Polignac number, because 661457757 - 2⁸ = 661457501 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 (661457707) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 37669 + ... + 52362.

It is an arithmetic number, because the mean of its divisors is an integer number (57620480).

Almost surely, 2^661457757 is an apocalyptic number.

It is an amenable number.

661457757 is a deficient number, since it is larger than the sum of its proper divisors (260469923).

661457757 is a wasteful number, since it uses less digits than its factorization.

661457757 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90144.

The product of its digits is 1234800, while the sum is 48.

The square root of 661457757 is about 25718.8210655154. The cubic root of 661457757 is about 871.2993123581.

The spelling of 661457757 in words is "six hundred sixty-one million, four hundred fifty-seven thousand, seven hundred fifty-seven".