3155696921 has 4 divisors (see below), whose sum is σ = 3398442852. Its totient is φ = 2912950992.

The previous prime is 3155696917. The next prime is 3155696923. The reversal of 3155696921 is 1296965513.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1972336921 + 1183360000 = 44411^2 + 34400^2 .

It is a cyclic number.

It is not a de Polignac number, because 3155696921 - 2² = 3155696917 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3155696923) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 121372946 + ... + 121372971.

It is an arithmetic number, because the mean of its divisors is an integer number (849610713).

Almost surely, 2^3155696921 is an apocalyptic number.

It is an amenable number.

3155696921 is a deficient number, since it is larger than the sum of its proper divisors (242745931).

3155696921 is a wasteful number, since it uses less digits than its factorization.

3155696921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 242745930.

The product of its digits is 437400, while the sum is 47.

The square root of 3155696921 is about 56175.5900814580. The cubic root of 3155696921 is about 1466.7803910152.

The spelling of 3155696921 in words is "three billion, one hundred fifty-five million, six hundred ninety-six thousand, nine hundred twenty-one".