661913492 has 12 divisors (see below), whose sum is σ = 1158792180. Its totient is φ = 330830016.

The previous prime is 661913467. The next prime is 661913503. The reversal of 661913492 is 294319166.

It can be written as a sum of positive squares in 2 ways, for example, as 648924676 + 12988816 = 25474^2 + 3604^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19403 + ... + 41234.

It is an arithmetic number, because the mean of its divisors is an integer number (96566015).

Almost surely, 2^661913492 is an apocalyptic number.

It is an amenable number.

661913492 is a deficient number, since it is larger than the sum of its proper divisors (496878688).

661913492 is a wasteful number, since it uses less digits than its factorization.

661913492 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63370 (or 63368 counting only the distinct ones).

The product of its digits is 69984, while the sum is 41.

The square root of 661913492 is about 25727.6794911628. The cubic root of 661913492 is about 871.4993707031.

The spelling of 661913492 in words is "six hundred sixty-one million, nine hundred thirteen thousand, four hundred ninety-two".