121605389 has 2 divisors, whose sum is σ = 121605390. Its totient is φ = 121605388.

The previous prime is 121605359. The next prime is 121605397. The reversal of 121605389 is 983506121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 112254025 + 9351364 = 10595^2 + 3058^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121605389 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121605329) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60802694 + 60802695.

It is an arithmetic number, because the mean of its divisors is an integer number (60802695).

Almost surely, 2^121605389 is an apocalyptic number.

It is an amenable number.

121605389 is a deficient number, since it is larger than the sum of its proper divisors (1).

121605389 is an equidigital number, since it uses as much as digits as its factorization.

121605389 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12960, while the sum is 35.

The square root of 121605389 is about 11027.4833484345. The cubic root of 121605389 is about 495.4322503979.

The spelling of 121605389 in words is "one hundred twenty-one million, six hundred five thousand, three hundred eighty-nine".