1661901924 has 12 divisors (see below), whose sum is σ = 3877771184. Its totient is φ = 553967304.

The previous prime is 1661901893. The next prime is 1661901949. The reversal of 1661901924 is 4291091661.

It is a tau number, because it is divible by the number of its divisors (12).

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, 69245902 + ... + 69245925.

Almost surely, 2^1661901924 is an apocalyptic number.

It is an amenable number.

1661901924 is an abundant number, since it is smaller than the sum of its proper divisors (2215869260).

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

1661901924 is a wasteful number, since it uses less digits than its factorization.

1661901924 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 138491834 (or 138491832 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 39.

The square root of 1661901924 is about 40766.4313375601. The cubic root of 1661901924 is about 1184.5001776796.

The spelling of 1661901924 in words is "one billion, six hundred sixty-one million, nine hundred one thousand, nine hundred twenty-four".