4351851921 has 4 divisors (see below), whose sum is σ = 5802469232. Its totient is φ = 2901234612.

The previous prime is 4351851887. The next prime is 4351851929. The reversal of 4351851921 is 1291581534.

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 4351851921 - 2⁷ = 4351851793 is a prime.

It is a super-2 number, since 2×4351851921² = 37877230284622780482, 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 4351851921.

It is not an unprimeable number, because it can be changed into a prime (4351851929) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 725308651 + ... + 725308656.

It is an arithmetic number, because the mean of its divisors is an integer number (1450617308).

Almost surely, 2^4351851921 is an apocalyptic number.

It is an amenable number.

4351851921 is a deficient number, since it is larger than the sum of its proper divisors (1450617311).

4351851921 is a wasteful number, since it uses less digits than its factorization.

4351851921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1450617310.

The product of its digits is 43200, while the sum is 39.

The square root of 4351851921 is about 65968.5676743099. The cubic root of 4351851921 is about 1632.6435231732.

The spelling of 4351851921 in words is "four billion, three hundred fifty-one million, eight hundred fifty-one thousand, nine hundred twenty-one".