121316553663 has 4 divisors (see below), whose sum is σ = 161755404888. Its totient is φ = 80877702440.

The previous prime is 121316553661. The next prime is 121316553691. The reversal of 121316553663 is 366355613121.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 366355613121 = 3 ⋅122118537707.

It is a cyclic number.

It is not a de Polignac number, because 121316553663 - 2¹ = 121316553661 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121316553661) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20219425608 + ... + 20219425613.

It is an arithmetic number, because the mean of its divisors is an integer number (40438851222).

Almost surely, 2^121316553663 is an apocalyptic number.

121316553663 is a deficient number, since it is larger than the sum of its proper divisors (40438851225).

121316553663 is an equidigital number, since it uses as much as digits as its factorization.

121316553663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40438851224.

The product of its digits is 291600, while the sum is 42.

The spelling of 121316553663 in words is "one hundred twenty-one billion, three hundred sixteen million, five hundred fifty-three thousand, six hundred sixty-three".