121749128658 has 24 divisors (see below), whose sum is σ = 267726942288. Its totient is φ = 39977325432.

The previous prime is 121749128653. The next prime is 121749128689. The reversal of 121749128658 is 856821947121.

121749128658 is a `hidden beast` number, since 1 + 21 + 7 + 491 + 2 + 86 + 58 = 666.

It is not an unprimeable number, because it can be changed into a prime (121749128653) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 50475216 + ... + 50477627.

It is an arithmetic number, because the mean of its divisors is an integer number (11155289262).

Almost surely, 2^121749128658 is an apocalyptic number.

121749128658 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

121749128658 is an abundant number, since it is smaller than the sum of its proper divisors (145977813630).

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

121749128658 is a wasteful number, since it uses less digits than its factorization.

121749128658 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 100952918 (or 100952915 counting only the distinct ones).

The product of its digits is 1935360, while the sum is 54.

The spelling of 121749128658 in words is "one hundred twenty-one billion, seven hundred forty-nine million, one hundred twenty-eight thousand, six hundred fifty-eight".