1851332921 has 2 divisors, whose sum is σ = 1851332922. Its totient is φ = 1851332920.

The previous prime is 1851332911. The next prime is 1851332941. The reversal of 1851332921 is 1292331581.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1710649600 + 140683321 = 41360^2 + 11861^2 .

It is a cyclic number.

It is not a de Polignac number, because 1851332921 - 2¹⁰ = 1851331897 is a prime.

It is not a weakly prime, because it can be changed into another prime (1851332911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 925666460 + 925666461.

It is an arithmetic number, because the mean of its divisors is an integer number (925666461).

Almost surely, 2^1851332921 is an apocalyptic number.

It is an amenable number.

1851332921 is a deficient number, since it is larger than the sum of its proper divisors (1).

1851332921 is an equidigital number, since it uses as much as digits as its factorization.

1851332921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12960, while the sum is 35.

The square root of 1851332921 is about 43027.1184370973. The cubic root of 1851332921 is about 1227.8957833745.

The spelling of 1851332921 in words is "one billion, eight hundred fifty-one million, three hundred thirty-two thousand, nine hundred twenty-one".