18970814781 has 12 divisors (see below), whose sum is σ = 27439681308. Its totient is φ = 12629951424.

The previous prime is 18970814773. The next prime is 18970814789. The reversal of 18970814781 is 18741807981.

18970814781 is a `hidden beast` number, since 1 + 8 + 97 + 0 + 81 + 478 + 1 = 666.

It is an interprime number because it is at equal distance from previous prime (18970814773) and next prime (18970814789).

It can be written as a sum of positive squares in 2 ways, for example, as 17884782756 + 1086032025 = 133734^2 + 32955^2 .

It is not a de Polignac number, because 18970814781 - 2³ = 18970814773 is a prime.

It is a super-2 number, since 2×18970814781² (a number of 21 digits) contains 22 as substring.

It is a hoax number, since the sum of its digits (54) coincides with the sum of the digits of its distinct prime factors.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18970814789) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1431240 + ... + 1444433.

It is an arithmetic number, because the mean of its divisors is an integer number (2286640109).

Almost surely, 2^18970814781 is an apocalyptic number.

It is an amenable number.

18970814781 is a deficient number, since it is larger than the sum of its proper divisors (8468866527).

18970814781 is a wasteful number, since it uses less digits than its factorization.

18970814781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2876412 (or 2876409 counting only the distinct ones).

The product of its (nonzero) digits is 903168, while the sum is 54.

The spelling of 18970814781 in words is "eighteen billion, nine hundred seventy million, eight hundred fourteen thousand, seven hundred eighty-one".