100121280779520 has 3888 divisors, whose sum is σ = 482905506912192. Its totient is φ = 18926520238080.

The previous prime is 100121280779519. The next prime is 100121280779537. The reversal of 100121280779520 is 25977082121001.

100121280779520 is a `hidden beast` number, since 10 + 0 + 1 + 21 + 28 + 0 + 7 + 79 + 520 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 431 ways as a sum of consecutive naturals, for example, 76603886707 + ... + 76603888013.

It is an arithmetic number, because the mean of its divisors is an integer number (124204091284).

Almost surely, 2^{100121280779520} is an apocalyptic number.

100121280779520 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 100121280779520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (241452753456096).

100121280779520 is an abundant number, since it is smaller than the sum of its proper divisors (382784226132672).

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

100121280779520 is a wasteful number, since it uses less digits than its factorization.

100121280779520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1458 (or 1421 counting only the distinct ones).

The product of its (nonzero) digits is 141120, while the sum is 45.

The spelling of 100121280779520 in words is "one hundred trillion, one hundred twenty-one billion, two hundred eighty million, seven hundred seventy-nine thousand, five hundred twenty".