121172391648 has 1296 divisors, whose sum is σ = 483608243664. Its totient is φ = 28426567680.

The previous prime is 121172391629. The next prime is 121172391679. The reversal of 121172391648 is 846193271121.

121172391648 is a `hidden beast` number, since 1 + 211 + 7 + 2 + 391 + 6 + 48 = 666.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 215 ways as a sum of consecutive naturals, for example, 1659895740 + ... + 1659895812.

It is an arithmetic number, because the mean of its divisors is an integer number (373154509).

Almost surely, 2^121172391648 is an apocalyptic number.

121172391648 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 121172391648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (241804121832).

121172391648 is an abundant number, since it is smaller than the sum of its proper divisors (362435852016).

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

121172391648 is a wasteful number, since it uses less digits than its factorization.

121172391648 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 185 (or 150 counting only the distinct ones).

The product of its digits is 145152, while the sum is 45.

The spelling of 121172391648 in words is "one hundred twenty-one billion, one hundred seventy-two million, three hundred ninety-one thousand, six hundred forty-eight".