1661335669 has 16 divisors (see below), whose sum is σ = 1910398336. Its totient is φ = 1415232000.

The previous prime is 1661335657. The next prime is 1661335681. The reversal of 1661335669 is 9665331661.

It is an interprime number because it is at equal distance from previous prime (1661335657) and next prime (1661335681).

It is not a de Polignac number, because 1661335669 - 2⁷ = 1661335541 is a prime.

It is a super-2 number, since 2×1661335669² = 5520072410183355122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1661335619) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1580194 + ... + 1581244.

It is an arithmetic number, because the mean of its divisors is an integer number (119399896).

Almost surely, 2^1661335669 is an apocalyptic number.

1661335669 is the 23533-rd hex number.

It is an amenable number.

1661335669 is a deficient number, since it is larger than the sum of its proper divisors (249062667).

1661335669 is a wasteful number, since it uses less digits than its factorization.

1661335669 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2236.

The product of its digits is 524880, while the sum is 46.

The square root of 1661335669 is about 40759.4856321814. The cubic root of 1661335669 is about 1184.3656319660.

The spelling of 1661335669 in words is "one billion, six hundred sixty-one million, three hundred thirty-five thousand, six hundred sixty-nine".