661001607 has 32 divisors (see below), whose sum is σ = 1121702400. Its totient is φ = 376856064.

The previous prime is 661001597. The next prime is 661001609. The reversal of 661001607 is 706100166.

661001607 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 661001607 - 2⁸ = 661001351 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661001609) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 84519 + ... + 92007.

It is an arithmetic number, because the mean of its divisors is an integer number (35053200).

Almost surely, 2^661001607 is an apocalyptic number.

661001607 is a deficient number, since it is larger than the sum of its proper divisors (460700793).

661001607 is a wasteful number, since it uses less digits than its factorization.

661001607 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7972 (or 7966 counting only the distinct ones).

The product of its (nonzero) digits is 1512, while the sum is 27.

The square root of 661001607 is about 25709.9515168738. The cubic root of 661001607 is about 871.0989797983.

The spelling of 661001607 in words is "six hundred sixty-one million, one thousand, six hundred seven".