661907315 has 4 divisors (see below), whose sum is σ = 794288784. Its totient is φ = 529525848.

The previous prime is 661907273. The next prime is 661907347. The reversal of 661907315 is 513709166.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 661907315 - 2¹² = 661903219 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 66190727 + ... + 66190736.

It is an arithmetic number, because the mean of its divisors is an integer number (198572196).

Almost surely, 2^661907315 is an apocalyptic number.

661907315 is a deficient number, since it is larger than the sum of its proper divisors (132381469).

661907315 is a wasteful number, since it uses less digits than its factorization.

661907315 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 132381468.

The product of its (nonzero) digits is 34020, while the sum is 38.

The square root of 661907315 is about 25727.5594450776. The cubic root of 661907315 is about 871.4966597404.

The spelling of 661907315 in words is "six hundred sixty-one million, nine hundred seven thousand, three hundred fifteen".