18851290981 has 8 divisors (see below), whose sum is σ = 19672289280. Its totient is φ = 18030407472.

The previous prime is 18851290979. The next prime is 18851291021. The reversal of 18851290981 is 18909215881.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 18851290981 - 2¹ = 18851290979 is a prime.

It is a super-2 number, since 2×18851290981² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18851090981) 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, 602971 + ... + 633463.

It is an arithmetic number, because the mean of its divisors is an integer number (2459036160).

Almost surely, 2^18851290981 is an apocalyptic number.

It is an amenable number.

18851290981 is a deficient number, since it is larger than the sum of its proper divisors (820998299).

18851290981 is a wasteful number, since it uses less digits than its factorization.

18851290981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57395.

The product of its (nonzero) digits is 414720, while the sum is 52.

The spelling of 18851290981 in words is "eighteen billion, eight hundred fifty-one million, two hundred ninety thousand, nine hundred eighty-one".