1812025981 has 8 divisors (see below), whose sum is σ = 1871251200. Its totient is φ = 1752849120.

The previous prime is 1812025939. The next prime is 1812025987. The reversal of 1812025981 is 1895202181.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1812025981 - 2¹⁵ = 1811993213 is a prime.

It is a super-2 number, since 2×1812025981² = 6566876311638024722, 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 1812025981.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1812025987) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 73890 + ... + 95308.

It is an arithmetic number, because the mean of its divisors is an integer number (233906400).

Almost surely, 2^1812025981 is an apocalyptic number.

It is an amenable number.

1812025981 is a deficient number, since it is larger than the sum of its proper divisors (59225219).

1812025981 is a wasteful number, since it uses less digits than its factorization.

1812025981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24179.

The product of its (nonzero) digits is 11520, while the sum is 37.

The square root of 1812025981 is about 42567.8984799579. The cubic root of 1812025981 is about 1219.1434417979.

The spelling of 1812025981 in words is "one billion, eight hundred twelve million, twenty-five thousand, nine hundred eighty-one".