61221512212 has 24 divisors (see below), whose sum is σ = 126665199360. Its totient is φ = 25333039200.

The previous prime is 61221512203. The next prime is 61221512239. The reversal of 61221512212 is 21221512216.

It is a super-4 number, since 4×61221512212⁴ (a number of 44 digits) contains 4444 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, 37697164 + ... + 37698787.

It is an arithmetic number, because the mean of its divisors is an integer number (5277716640).

Almost surely, 2^61221512212 is an apocalyptic number.

It is an amenable number.

61221512212 is an abundant number, since it is smaller than the sum of its proper divisors (65443687148).

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

61221512212 is a wasteful number, since it uses less digits than its factorization.

61221512212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 75395991 (or 75395989 counting only the distinct ones).

The product of its digits is 960, while the sum is 25.

The spelling of 61221512212 in words is "sixty-one billion, two hundred twenty-one million, five hundred twelve thousand, two hundred twelve".