661477597 has 12 divisors (see below), whose sum is σ = 750537088. Its totient is φ = 581941800.

The previous prime is 661477591. The next prime is 661477613. The reversal of 661477597 is 795774166.

It is not a de Polignac number, because 661477597 - 2¹⁹ = 660953309 is a prime.

It is a super-2 number, since 2×661477597² = 875105222665788818, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661477591) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 84423 + ... + 91924.

Almost surely, 2^661477597 is an apocalyptic number.

It is an amenable number.

661477597 is a deficient number, since it is larger than the sum of its proper divisors (89059491).

661477597 is a wasteful number, since it uses less digits than its factorization.

661477597 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 176400 (or 176389 counting only the distinct ones).

The product of its digits is 2222640, while the sum is 52.

The square root of 661477597 is about 25719.2067723715. The cubic root of 661477597 is about 871.3080236252.

The spelling of 661477597 in words is "six hundred sixty-one million, four hundred seventy-seven thousand, five hundred ninety-seven".