121687987 has 2 divisors, whose sum is σ = 121687988. Its totient is φ = 121687986.

The previous prime is 121687939. The next prime is 121687991. The reversal of 121687987 is 789786121.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 121687987 - 2⁷ = 121687859 is a prime.

It is a super-2 number, since 2×121687987² = 29615932360224338, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 121687987.

It is not a weakly prime, because it can be changed into another prime (121697987) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60843993 + 60843994.

It is an arithmetic number, because the mean of its divisors is an integer number (60843994).

Almost surely, 2^121687987 is an apocalyptic number.

121687987 is a deficient number, since it is larger than the sum of its proper divisors (1).

121687987 is an equidigital number, since it uses as much as digits as its factorization.

121687987 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 338688, while the sum is 49.

The square root of 121687987 is about 11031.2278101760. The cubic root of 121687987 is about 495.5443957882.

The spelling of 121687987 in words is "one hundred twenty-one million, six hundred eighty-seven thousand, nine hundred eighty-seven".