3551131621 has 4 divisors (see below), whose sum is σ = 3705528672. Its totient is φ = 3396734572.

The previous prime is 3551131609. The next prime is 3551131627. The reversal of 3551131621 is 1261311553.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 3551131621 - 2⁹ = 3551131109 is a prime.

It is a super-2 number, since 2×3551131621² = 25221071579332175282, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 3551131621.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3551131627) 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, 77198491 + ... + 77198536.

It is an arithmetic number, because the mean of its divisors is an integer number (926382168).

Almost surely, 2^3551131621 is an apocalyptic number.

It is an amenable number.

3551131621 is a deficient number, since it is larger than the sum of its proper divisors (154397051).

3551131621 is a wasteful number, since it uses less digits than its factorization.

3551131621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 154397050.

The product of its digits is 2700, while the sum is 28.

The square root of 3551131621 is about 59591.3720348844. The cubic root of 3551131621 is about 1525.6523764042.

The spelling of 3551131621 in words is "three billion, five hundred fifty-one million, one hundred thirty-one thousand, six hundred twenty-one".