660616631 has 4 divisors (see below), whose sum is σ = 674672352. Its totient is φ = 646560912.

The previous prime is 660616613. The next prime is 660616637. The reversal of 660616631 is 136616066.

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 660616631 - 2¹⁰ = 660615607 is a prime.

It is a super-2 number, since 2×660616631² = 872828666307580322, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 660616591 and 660616600.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (660616637) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7027790 + ... + 7027883.

It is an arithmetic number, because the mean of its divisors is an integer number (168668088).

Almost surely, 2^660616631 is an apocalyptic number.

660616631 is a deficient number, since it is larger than the sum of its proper divisors (14055721).

660616631 is a wasteful number, since it uses less digits than its factorization.

660616631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14055720.

The product of its (nonzero) digits is 23328, while the sum is 35.

The square root of 660616631 is about 25702.4635200597. The cubic root of 660616631 is about 870.9298338018.

The spelling of 660616631 in words is "six hundred sixty million, six hundred sixteen thousand, six hundred thirty-one".