21207307035181 has 8 divisors (see below), whose sum is σ = 22007800413720. Its totient is φ = 20411427451968.

The previous prime is 21207307035157. The next prime is 21207307035197. The reversal of 21207307035181 is 18153070370212.

It can be written as a sum of positive squares in 4 ways, for example, as 4116978973156 + 17090328062025 = 2029034^2 + 4134045^2 .

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 21207307035181 - 2⁵ = 21207307035149 is a prime.

It is a super-2 number, since 2×21207307035181² (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 (21207307032181) 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, 1153439466 + ... + 1153457851.

It is an arithmetic number, because the mean of its divisors is an integer number (2750975051715).

Almost surely, 2^{21207307035181} is an apocalyptic number.

It is an amenable number.

21207307035181 is a deficient number, since it is larger than the sum of its proper divisors (800493378539).

21207307035181 is a wasteful number, since it uses less digits than its factorization.

21207307035181 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2306897663.

The product of its (nonzero) digits is 70560, while the sum is 40.

The spelling of 21207307035181 in words is "twenty-one trillion, two hundred seven billion, three hundred seven million, thirty-five thousand, one hundred eighty-one".