61521312012 has 24 divisors (see below), whose sum is σ = 148180365312. Its totient is φ = 19845584400.

The previous prime is 61521311993. The next prime is 61521312059. The reversal of 61521312012 is 21021312516.

It is a happy number.

61521312012 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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, 82689564 + ... + 82690307.

It is an arithmetic number, because the mean of its divisors is an integer number (6174181888).

Almost surely, 2^61521312012 is an apocalyptic number.

61521312012 is a gapful number since it is divisible by the number (62) formed by its first and last digit.

It is an amenable number.

61521312012 is an abundant number, since it is smaller than the sum of its proper divisors (86659053300).

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

61521312012 is a wasteful number, since it uses less digits than its factorization.

61521312012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 165379909 (or 165379907 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 24.

Adding to 61521312012 its reverse (21021312516), we get a palindrome (82542624528).

The spelling of 61521312012 in words is "sixty-one billion, five hundred twenty-one million, three hundred twelve thousand, twelve".