661347599 has 8 divisors (see below), whose sum is σ = 723653760. Its totient is φ = 599405400.

The previous prime is 661347593. The next prime is 661347607. The reversal of 661347599 is 995743166.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-661347599 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 (661347593) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 87179 + ... + 94460.

It is an arithmetic number, because the mean of its divisors is an integer number (90456720).

Almost surely, 2^661347599 is an apocalyptic number.

661347599 is a deficient number, since it is larger than the sum of its proper divisors (62306161).

661347599 is a wasteful number, since it uses less digits than its factorization.

661347599 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 181981.

The product of its digits is 1224720, while the sum is 50.

The square root of 661347599 is about 25716.6793929543. The cubic root of 661347599 is about 871.2509414595.

The spelling of 661347599 in words is "six hundred sixty-one million, three hundred forty-seven thousand, five hundred ninety-nine".