121739904 has 192 divisors, whose sum is σ = 412120800. Its totient is φ = 34007040.

The previous prime is 121739903. The next prime is 121739921. The reversal of 121739904 is 409937121.

It is a tau number, because it is divible by the number of its divisors (192).

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

It is not an unprimeable number, because it can be changed into a prime (121739903) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 164367 + ... + 165105.

Almost surely, 2^121739904 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 121739904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (206060400).

121739904 is an abundant number, since it is smaller than the sum of its proper divisors (290380896).

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

121739904 is a wasteful number, since it uses less digits than its factorization.

121739904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 783 (or 768 counting only the distinct ones).

The product of its (nonzero) digits is 13608, while the sum is 36.

The square root of 121739904 is about 11033.5807424426. The cubic root of 121739904 is about 495.6148588392.

The spelling of 121739904 in words is "one hundred twenty-one million, seven hundred thirty-nine thousand, nine hundred four".