121651405812 has 36 divisors (see below), whose sum is σ = 309571544100. Its totient is φ = 40278316032.

The previous prime is 121651405793. The next prime is 121651405829. The reversal of 121651405812 is 218504156121.

121651405812 is a `hidden beast` number, since 1 + 2 + 1 + 65 + 14 + 0 + 581 + 2 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 71077692816 + 50573712996 = 266604^2 + 224886^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 11334253 + ... + 11344980.

Almost surely, 2^121651405812 is an apocalyptic number.

121651405812 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

121651405812 is an abundant number, since it is smaller than the sum of its proper divisors (187920138288).

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

121651405812 is a wasteful number, since it uses less digits than its factorization.

121651405812 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22679392 (or 22679387 counting only the distinct ones).

The product of its (nonzero) digits is 19200, while the sum is 36.

The spelling of 121651405812 in words is "one hundred twenty-one billion, six hundred fifty-one million, four hundred five thousand, eight hundred twelve".