21018134181 has 8 divisors (see below), whose sum is σ = 30571831584. Its totient is φ = 12738263120.

The previous prime is 21018134167. The next prime is 21018134201. The reversal of 21018134181 is 18143181012.

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

It is not a de Polignac number, because 21018134181 - 2¹⁷ = 21018003109 is a prime.

It is a super-2 number, since 2×21018134181² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21018134281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 318456546 + ... + 318456611.

It is an arithmetic number, because the mean of its divisors is an integer number (3821478948).

Almost surely, 2^21018134181 is an apocalyptic number.

It is an amenable number.

21018134181 is a deficient number, since it is larger than the sum of its proper divisors (9553697403).

21018134181 is a wasteful number, since it uses less digits than its factorization.

21018134181 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 636913171.

The product of its (nonzero) digits is 1536, while the sum is 30.

The spelling of 21018134181 in words is "twenty-one billion, eighteen million, one hundred thirty-four thousand, one hundred eighty-one".