81122020212 has 24 divisors (see below), whose sum is σ = 189612779776. Its totient is φ = 26993806848.

The previous prime is 81122020201. The next prime is 81122020237. The reversal of 81122020212 is 21202022118.

It is a super-2 number, since 2×81122020212² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5851108 + ... + 5864955.

Almost surely, 2^81122020212 is an apocalyptic number.

It is an amenable number.

81122020212 is an abundant number, since it is smaller than the sum of its proper divisors (108490759564).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81122020212 is a wasteful number, since it uses less digits than its factorization.

81122020212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11716647 (or 11716645 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 21.

The spelling of 81122020212 in words is "eighty-one billion, one hundred twenty-two million, twenty thousand, two hundred twelve".