661694424 has 32 divisors (see below), whose sum is σ = 1671295920. Its totient is φ = 218290176.

The previous prime is 661694393. The next prime is 661694447. The reversal of 661694424 is 424496166.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 139789 + ... + 144444.

Almost surely, 2^661694424 is an apocalyptic number.

It is an amenable number.

661694424 is an abundant number, since it is smaller than the sum of its proper divisors (1009601496).

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

661694424 is a wasteful number, since it uses less digits than its factorization.

661694424 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 284339 (or 284335 counting only the distinct ones).

The product of its digits is 248832, while the sum is 42.

The square root of 661694424 is about 25723.4217008547. The cubic root of 661694424 is about 871.4032157965.

The spelling of 661694424 in words is "six hundred sixty-one million, six hundred ninety-four thousand, four hundred twenty-four".