1851222144 has 64 divisors (see below), whose sum is σ = 4997983680. Its totient is φ = 606950400.

The previous prime is 1851222103. The next prime is 1851222151. The reversal of 1851222144 is 4412221581.

It is a tau number, because it is divible by the number of its divisors (64).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16092 + ... + 62939.

It is an arithmetic number, because the mean of its divisors is an integer number (78093495).

Almost surely, 2^1851222144 is an apocalyptic number.

It is an amenable number.

1851222144 is an abundant number, since it is smaller than the sum of its proper divisors (3146761536).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1851222144 is an equidigital number, since it uses as much as digits as its factorization.

1851222144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79109 (or 79097 counting only the distinct ones).

The product of its digits is 5120, while the sum is 30.

The square root of 1851222144 is about 43025.8311250346. The cubic root of 1851222144 is about 1227.8712919531.

The spelling of 1851222144 in words is "one billion, eight hundred fifty-one million, two hundred twenty-two thousand, one hundred forty-four".