121291612440 has 64 divisors (see below), whose sum is σ = 363914933760. Its totient is φ = 32340865920.

The previous prime is 121291612423. The next prime is 121291612447. The reversal of 121291612440 is 44216192121.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121291612447) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1145335 + ... + 1246745.

It is an arithmetic number, because the mean of its divisors is an integer number (5686170840).

Almost surely, 2^121291612440 is an apocalyptic number.

121291612440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

121291612440 is an abundant number, since it is smaller than the sum of its proper divisors (242623321320).

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

121291612440 is a wasteful number, since it uses less digits than its factorization.

121291612440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111392 (or 111388 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 33.

The spelling of 121291612440 in words is "one hundred twenty-one billion, two hundred ninety-one million, six hundred twelve thousand, four hundred forty".