1661325219 has 12 divisors (see below), whose sum is σ = 2400103992. Its totient is φ = 1107360000.

The previous prime is 1661325203. The next prime is 1661325241. The reversal of 1661325219 is 9125231661.

1661325219 is a `hidden beast` number, since 1 + 6 + 613 + 25 + 2 + 19 = 666.

It is not a de Polignac number, because 1661325219 - 2⁴ = 1661325203 is a prime.

It is a super-2 number, since 2×1661325219² = 5520002966570795922, which contains 22 as substring.

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

It is not an unprimeable number, because it can be changed into a prime (1661325019) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 57219 + ... + 81219.

It is an arithmetic number, because the mean of its divisors is an integer number (200008666).

Almost surely, 2^1661325219 is an apocalyptic number.

1661325219 is a deficient number, since it is larger than the sum of its proper divisors (738778773).

1661325219 is a wasteful number, since it uses less digits than its factorization.

1661325219 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31698 (or 31695 counting only the distinct ones).

The product of its digits is 19440, while the sum is 36.

The square root of 1661325219 is about 40759.3574409607. The cubic root of 1661325219 is about 1184.3631486936.

The spelling of 1661325219 in words is "one billion, six hundred sixty-one million, three hundred twenty-five thousand, two hundred nineteen".