17790991253981 has 32 divisors (see below), whose sum is σ = 20754922076928. Its totient is φ = 15070537405440.

The previous prime is 17790991253951. The next prime is 17790991254013. The reversal of 17790991253981 is 18935219909771.

It is a de Polignac number, because none of the positive numbers 2^k-17790991253981 is a prime.

It is a super-2 number, since 2×17790991253981² (a number of 27 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 (17790991253921) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 75327431 + ... + 75563243.

It is an arithmetic number, because the mean of its divisors is an integer number (648591314904).

Almost surely, 2^{17790991253981} is an apocalyptic number.

17790991253981 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

17790991253981 is a deficient number, since it is larger than the sum of its proper divisors (2963930822947).

17790991253981 is a wasteful number, since it uses less digits than its factorization.

17790991253981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 239861.

The product of its (nonzero) digits is 77157360, while the sum is 71.

The spelling of 17790991253981 in words is "seventeen trillion, seven hundred ninety billion, nine hundred ninety-one million, two hundred fifty-three thousand, nine hundred eighty-one".