135777121920 has 384 divisors, whose sum is σ = 523963702080. Its totient is φ = 32112230400.

The previous prime is 135777121897. The next prime is 135777121939. The reversal of 135777121920 is 29121777531.

135777121920 is a `hidden beast` number, since 1 + 3 + 577 + 71 + 2 + 1 + 9 + 2 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (384).

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

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2571627 + ... + 2623893.

Almost surely, 2^135777121920 is an apocalyptic number.

135777121920 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 135777121920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (261981851040).

135777121920 is an abundant number, since it is smaller than the sum of its proper divisors (388186580160).

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

135777121920 is a wasteful number, since it uses less digits than its factorization.

135777121920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52344 (or 52329 counting only the distinct ones).

The product of its (nonzero) digits is 185220, while the sum is 45.

The spelling of 135777121920 in words is "one hundred thirty-five billion, seven hundred seventy-seven million, one hundred twenty-one thousand, nine hundred twenty".