121739391774 has 640 divisors, whose sum is σ = 385239343104. Its totient is φ = 27713664000.

The previous prime is 121739391757. The next prime is 121739391779. The reversal of 121739391774 is 477193937121.

121739391774 is a `hidden beast` number, since 1 + 217 + 39 + 391 + 7 + 7 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a self number, because there is not a number n which added to its sum of digits gives 121739391774.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121739391779) by changing a digit.

It is a polite number, since it can be written in 319 ways as a sum of consecutive naturals, for example, 306648144 + ... + 306648540.

Almost surely, 2^121739391774 is an apocalyptic number.

121739391774 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 121739391774, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (192619671552).

121739391774 is an abundant number, since it is smaller than the sum of its proper divisors (263499951330).

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

121739391774 is a wasteful number, since it uses less digits than its factorization.

121739391774 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 534 (or 525 counting only the distinct ones).

The product of its digits is 2000376, while the sum is 54.

The spelling of 121739391774 in words is "one hundred twenty-one billion, seven hundred thirty-nine million, three hundred ninety-one thousand, seven hundred seventy-four".