1661739929 has 8 divisors (see below), whose sum is σ = 1685020512. Its totient is φ = 1638537120.

The previous prime is 1661739917. The next prime is 1661739931. The reversal of 1661739929 is 9299371661.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1661739929 - 2⁴ = 1661739913 is a prime.

It is a super-2 number, since 2×1661739929² = 5522759183265850082, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1661739229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24269 + ... + 62549.

It is an arithmetic number, because the mean of its divisors is an integer number (210627564).

Almost surely, 2^1661739929 is an apocalyptic number.

It is an amenable number.

1661739929 is a deficient number, since it is larger than the sum of its proper divisors (23280583).

1661739929 is an equidigital number, since it uses as much as digits as its factorization.

1661739929 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38887.

The product of its digits is 1102248, while the sum is 53.

The square root of 1661739929 is about 40764.4444215790. Note that the first 4 decimals coincide. The cubic root of 1661739929 is about 1184.4616897804.

The spelling of 1661739929 in words is "one billion, six hundred sixty-one million, seven hundred thirty-nine thousand, nine hundred twenty-nine".