661677831 has 12 divisors (see below), whose sum is σ = 1006060120. Its totient is φ = 417901680.

The previous prime is 661677787. The next prime is 661677839. The reversal of 661677831 is 138776166.

661677831 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 661677831 - 2¹¹ = 661675783 is a prime.

It is a super-2 number, since 2×661677831² = 875635104073729122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661677839) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1934560 + ... + 1934901.

Almost surely, 2^661677831 is an apocalyptic number.

661677831 is a deficient number, since it is larger than the sum of its proper divisors (344382289).

661677831 is a wasteful number, since it uses less digits than its factorization.

661677831 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3869486 (or 3869483 counting only the distinct ones).

The product of its digits is 254016, while the sum is 45.

The square root of 661677831 is about 25723.0991717561. The cubic root of 661677831 is about 871.3959318126.

The spelling of 661677831 in words is "six hundred sixty-one million, six hundred seventy-seven thousand, eight hundred thirty-one".