1661049900 has 54 divisors (see below), whose sum is σ = 5206471452. Its totient is φ = 442946400.

The previous prime is 1661049883. The next prime is 1661049931. The reversal of 1661049900 is 99401661.

1661049900 is a `hidden beast` number, since 166 + 1 + 0 + 499 + 0 + 0 = 666.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

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

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 921906 + ... + 923705.

It is an arithmetic number, because the mean of its divisors is an integer number (96416138).

Almost surely, 2^1661049900 is an apocalyptic number.

1661049900 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1661049900 is an abundant number, since it is smaller than the sum of its proper divisors (3545421552).

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

1661049900 is a wasteful number, since it uses less digits than its factorization.

1661049900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1845631 (or 1845621 counting only the distinct ones).

The product of its (nonzero) digits is 11664, while the sum is 36.

The square root of 1661049900 is about 40755.9799293306. The cubic root of 1661049900 is about 1184.2977198644.

The spelling of 1661049900 in words is "one billion, six hundred sixty-one million, forty-nine thousand, nine hundred".