121993561 has 2 divisors, whose sum is σ = 121993562. Its totient is φ = 121993560.

The previous prime is 121993519. The next prime is 121993603. The reversal of 121993561 is 165399121.

It is a happy number.

It is a balanced prime because it is at equal distance from previous prime (121993519) and next prime (121993603).

It can be written as a sum of positive squares in only one way, i.e., 85451536 + 36542025 = 9244^2 + 6045^2 .

It is a cyclic number.

It is not a de Polignac number, because 121993561 - 2⁹ = 121993049 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 121993561.

It is not a weakly prime, because it can be changed into another prime (121996561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60996780 + 60996781.

It is an arithmetic number, because the mean of its divisors is an integer number (60996781).

Almost surely, 2^121993561 is an apocalyptic number.

It is an amenable number.

121993561 is a deficient number, since it is larger than the sum of its proper divisors (1).

121993561 is an equidigital number, since it uses as much as digits as its factorization.

121993561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 14580, while the sum is 37.

The square root of 121993561 is about 11045.0695335068. The cubic root of 121993561 is about 495.9588407248.

The spelling of 121993561 in words is "one hundred twenty-one million, nine hundred ninety-three thousand, five hundred sixty-one".