2135691921 has 16 divisors (see below), whose sum is σ = 3213581760. Its totient is φ = 1249725120.

The previous prime is 2135691917. The next prime is 2135691931. The reversal of 2135691921 is 1291965312.

It is not a de Polignac number, because 2135691921 - 2² = 2135691917 is a prime.

It is a super-2 number, since 2×2135691921² = 9122359962849340482, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 2135691921.

It is not an unprimeable number, because it can be changed into a prime (2135691931) 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, 1114870 + ... + 1116783.

It is an arithmetic number, because the mean of its divisors is an integer number (200848860).

Almost surely, 2^2135691921 is an apocalyptic number.

It is an amenable number.

2135691921 is a deficient number, since it is larger than the sum of its proper divisors (1077889839).

2135691921 is a wasteful number, since it uses less digits than its factorization.

2135691921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2231696.

The product of its digits is 29160, while the sum is 39.

The square root of 2135691921 is about 46213.5469424280. The cubic root of 2135691921 is about 1287.7934196113.

The spelling of 2135691921 in words is "two billion, one hundred thirty-five million, six hundred ninety-one thousand, nine hundred twenty-one".