121557487 has 2 divisors, whose sum is σ = 121557488. Its totient is φ = 121557486.

The previous prime is 121557481. The next prime is 121557503. The reversal of 121557487 is 784755121.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121557487 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 (121557481) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60778743 + 60778744.

It is an arithmetic number, because the mean of its divisors is an integer number (60778744).

Almost surely, 2^121557487 is an apocalyptic number.

121557487 is a deficient number, since it is larger than the sum of its proper divisors (1).

121557487 is an equidigital number, since it uses as much as digits as its factorization.

121557487 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 78400, while the sum is 40.

The square root of 121557487 is about 11025.3111974220. The cubic root of 121557487 is about 495.3671893764.

The spelling of 121557487 in words is "one hundred twenty-one million, five hundred fifty-seven thousand, four hundred eighty-seven".