121738391 has 2 divisors, whose sum is σ = 121738392. Its totient is φ = 121738390.

The previous prime is 121738373. The next prime is 121738451. The reversal of 121738391 is 193837121.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 121738391 - 2²² = 117544087 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121738691) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60869195 + 60869196.

It is an arithmetic number, because the mean of its divisors is an integer number (60869196).

Almost surely, 2^121738391 is an apocalyptic number.

121738391 is a deficient number, since it is larger than the sum of its proper divisors (1).

121738391 is an equidigital number, since it uses as much as digits as its factorization.

121738391 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9072, while the sum is 35.

The square root of 121738391 is about 11033.5121788123. The cubic root of 121738391 is about 495.6128056412.

The spelling of 121738391 in words is "one hundred twenty-one million, seven hundred thirty-eight thousand, three hundred ninety-one".