121562640540 has 288 divisors, whose sum is σ = 420873014016. Its totient is φ = 29207485440.

The previous prime is 121562640461. The next prime is 121562640599. The reversal of 121562640540 is 45046265121.

121562640540 is a `hidden beast` number, since 1 + 2 + 1 + 5 + 6 + 2 + 640 + 5 + 4 + 0 = 666.

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

It is a junction number, because it is equal to n+sod(n) for n = 121562640495 and 121562640504.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 6030919 + ... + 6051041.

It is an arithmetic number, because the mean of its divisors is an integer number (1461364632).

Almost surely, 2^121562640540 is an apocalyptic number.

121562640540 is a gapful number since it is divisible by the number (10) 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 121562640540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (210436507008).

121562640540 is an abundant number, since it is smaller than the sum of its proper divisors (299310373476).

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

121562640540 is a wasteful number, since it uses less digits than its factorization.

121562640540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20271 (or 20257 counting only the distinct ones).

The product of its (nonzero) digits is 57600, while the sum is 36.

The spelling of 121562640540 in words is "one hundred twenty-one billion, five hundred sixty-two million, six hundred forty thousand, five hundred forty".