121856243 has 2 divisors, whose sum is σ = 121856244. Its totient is φ = 121856242.

The previous prime is 121856239. The next prime is 121856249. The reversal of 121856243 is 342658121.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 121856243 - 2² = 121856239 is a prime.

It is not a weakly prime, because it can be changed into another prime (121856249) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60928121 + 60928122.

It is an arithmetic number, because the mean of its divisors is an integer number (60928122).

Almost surely, 2^121856243 is an apocalyptic number.

121856243 is a deficient number, since it is larger than the sum of its proper divisors (1).

121856243 is an equidigital number, since it uses as much as digits as its factorization.

121856243 is an evil number, because the sum of its binary digits is even.

The product of its digits is 11520, while the sum is 32.

The square root of 121856243 is about 11038.8515254079. The cubic root of 121856243 is about 495.7726843284.

The spelling of 121856243 in words is "one hundred twenty-one million, eight hundred fifty-six thousand, two hundred forty-three".