121557012019 has 2 divisors, whose sum is σ = 121557012020. Its totient is φ = 121557012018.

The previous prime is 121557011999. The next prime is 121557012067. The reversal of 121557012019 is 910210755121.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121557012019 is a prime.

It is a super-2 number, since 2×121557012019² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (121557012319) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60778506009 + 60778506010.

It is an arithmetic number, because the mean of its divisors is an integer number (60778506010).

Almost surely, 2^121557012019 is an apocalyptic number.

121557012019 is a deficient number, since it is larger than the sum of its proper divisors (1).

121557012019 is an equidigital number, since it uses as much as digits as its factorization.

121557012019 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6300, while the sum is 34.

The spelling of 121557012019 in words is "one hundred twenty-one billion, five hundred fifty-seven million, twelve thousand, nineteen".