661372701 has 16 divisors (see below), whose sum is σ = 965841408. Its totient is φ = 399230000.

The previous prime is 661372687. The next prime is 661372711. The reversal of 661372701 is 107273166.

It is a cyclic number.

It is not a de Polignac number, because 661372701 - 2²² = 657178397 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661372711) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 31641 + ... + 48206.

It is an arithmetic number, because the mean of its divisors is an integer number (60365088).

Almost surely, 2^661372701 is an apocalyptic number.

It is an amenable number.

661372701 is a deficient number, since it is larger than the sum of its proper divisors (304468707).

661372701 is a wasteful number, since it uses less digits than its factorization.

661372701 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80112.

The product of its (nonzero) digits is 10584, while the sum is 33.

The square root of 661372701 is about 25717.1674373365. The cubic root of 661372701 is about 871.2619643389.

The spelling of 661372701 in words is "six hundred sixty-one million, three hundred seventy-two thousand, seven hundred one".