3551857421 has 4 divisors (see below), whose sum is σ = 4059265632. Its totient is φ = 3044449212.

The previous prime is 3551857367. The next prime is 3551857433. The reversal of 3551857421 is 1247581553.

It is a happy number.

3551857421 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 not a de Polignac number, because 3551857421 - 2²⁶ = 3484748557 is a prime.

It is a super-2 number, since 2×3551857421² = 25231382278225542482, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3551857021) 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, 253704095 + ... + 253704108.

It is an arithmetic number, because the mean of its divisors is an integer number (1014816408).

Almost surely, 2^3551857421 is an apocalyptic number.

It is an amenable number.

3551857421 is a deficient number, since it is larger than the sum of its proper divisors (507408211).

3551857421 is an equidigital number, since it uses as much as digits as its factorization.

3551857421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 507408210.

The product of its digits is 168000, while the sum is 41.

The square root of 3551857421 is about 59597.4615315116. The cubic root of 3551857421 is about 1525.7563097586.

The spelling of 3551857421 in words is "three billion, five hundred fifty-one million, eight hundred fifty-seven thousand, four hundred twenty-one".