661692312 has 96 divisors (see below), whose sum is σ = 1853982000. Its totient is φ = 213034752.

The previous prime is 661692307. The next prime is 661692323. The reversal of 661692312 is 213296166.

It is a happy number.

661692312 is a `hidden beast` number, since 6 + 616 + 9 + 2 + 31 + 2 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 396103 + ... + 397769.

Almost surely, 2^661692312 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 661692312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (926991000).

661692312 is an abundant number, since it is smaller than the sum of its proper divisors (1192289688).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

661692312 is a wasteful number, since it uses less digits than its factorization.

661692312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1865 (or 1858 counting only the distinct ones).

The product of its digits is 23328, while the sum is 36.

The square root of 661692312 is about 25723.3806487406. The cubic root of 661692312 is about 871.4022886789.

The spelling of 661692312 in words is "six hundred sixty-one million, six hundred ninety-two thousand, three hundred twelve".