121557115573 has 2 divisors, whose sum is σ = 121557115574. Its totient is φ = 121557115572.

The previous prime is 121557115541. The next prime is 121557115607. The reversal of 121557115573 is 375511755121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 64466225604 + 57090889969 = 253902^2 + 238937^2 .

It is a cyclic number.

It is not a de Polignac number, because 121557115573 - 2⁵ = 121557115541 is a prime.

It is a super-2 number, since 2×121557115573² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (121557115513) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60778557786 + 60778557787.

It is an arithmetic number, because the mean of its divisors is an integer number (60778557787).

Almost surely, 2^121557115573 is an apocalyptic number.

It is an amenable number.

121557115573 is a deficient number, since it is larger than the sum of its proper divisors (1).

121557115573 is an equidigital number, since it uses as much as digits as its factorization.

121557115573 is an evil number, because the sum of its binary digits is even.

The product of its digits is 183750, while the sum is 43.

The spelling of 121557115573 in words is "one hundred twenty-one billion, five hundred fifty-seven million, one hundred fifteen thousand, five hundred seventy-three".