661090896 has 50 divisors (see below), whose sum is σ = 1913392602. Its totient is φ = 220363200.

The previous prime is 661090879. The next prime is 661090949. The reversal of 661090896 is 698090166.

661090896 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 427000896 + 234090000 = 20664^2 + 15300^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 253755 + ... + 256346.

Almost surely, 2^661090896 is an apocalyptic number.

It is an amenable number.

661090896 is an abundant number, since it is smaller than the sum of its proper divisors (1252301706).

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

661090896 is a wasteful number, since it uses less digits than its factorization.

661090896 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 510121 (or 510106 counting only the distinct ones).

The product of its (nonzero) digits is 139968, while the sum is 45.

The square root of 661090896 is about 25711.6879259219. The cubic root of 661090896 is about 871.1382011124.

The spelling of 661090896 in words is "six hundred sixty-one million, ninety thousand, eight hundred ninety-six".