1851166720 has 208 divisors, whose sum is σ = 5077764720. Its totient is φ = 641728512.

The previous prime is 1851166697. The next prime is 1851166739. The reversal of 1851166720 is 276611581.

It can be written as a sum of positive squares in 8 ways, for example, as 28901376 + 1822265344 = 5376^2 + 42688^2 .

It is a tau number, because it is divible by the number of its divisors (208).

It is a self number, because there is not a number n which added to its sum of digits gives 1851166720.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4525876 + ... + 4526284.

Almost surely, 2^1851166720 is an apocalyptic number.

1851166720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1851166720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2538882360).

1851166720 is an abundant number, since it is smaller than the sum of its proper divisors (3226598000).

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

1851166720 is a wasteful number, since it uses less digits than its factorization.

1851166720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 468 (or 446 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 37.

The square root of 1851166720 is about 43025.1870420106. The cubic root of 1851166720 is about 1227.8590380271.

The spelling of 1851166720 in words is "one billion, eight hundred fifty-one million, one hundred sixty-six thousand, seven hundred twenty".