12291985637505 has 108 divisors (see below), whose sum is σ = 25736608528020. Its totient is φ = 5619192699456.

The previous prime is 12291985637501. The next prime is 12291985637507. The reversal of 12291985637505 is 50573658919221.

12291985637505 is a `hidden beast` number, since 1 + 2 + 2 + 9 + 1 + 98 + 5 + 6 + 37 + 505 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 5790510697104 + 6501474940401 = 2406348^2 + 2549799^2 .

It is not a de Polignac number, because 12291985637505 - 2² = 12291985637501 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is not an unprimeable number, because it can be changed into a prime (12291985637501) by changing a digit.

It is a polite number, since it can be written in 107 ways as a sum of consecutive naturals, for example, 2216010 + ... + 5430899.

It is an arithmetic number, because the mean of its divisors is an integer number (238301930815).

Almost surely, 2^{12291985637505} is an apocalyptic number.

12291985637505 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

12291985637505 is an abundant number, since it is smaller than the sum of its proper divisors (13444622890515).

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

12291985637505 is an frugal number, since it uses more digits than its factorization.

12291985637505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7646952 (or 7646924 counting only the distinct ones).

The product of its (nonzero) digits is 40824000, while the sum is 63.

The spelling of 12291985637505 in words is "twelve trillion, two hundred ninety-one billion, nine hundred eighty-five million, six hundred thirty-seven thousand, five hundred five".