121420391 has 2 divisors, whose sum is σ = 121420392. Its totient is φ = 121420390.

The previous prime is 121420373. The next prime is 121420501. The reversal of 121420391 is 193024121.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121420391 is a prime.

It is a super-2 number, since 2×121420391² = 29485822701185762, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121420331) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60710195 + 60710196.

It is an arithmetic number, because the mean of its divisors is an integer number (60710196).

Almost surely, 2^121420391 is an apocalyptic number.

121420391 is a deficient number, since it is larger than the sum of its proper divisors (1).

121420391 is an equidigital number, since it uses as much as digits as its factorization.

121420391 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 432, while the sum is 23.

The square root of 121420391 is about 11019.0921132369. The cubic root of 121420391 is about 495.1808895736.

The spelling of 121420391 in words is "one hundred twenty-one million, four hundred twenty thousand, three hundred ninety-one".