121263556461 has 4 divisors (see below), whose sum is σ = 161684741952. Its totient is φ = 80842370972.

The previous prime is 121263556459. The next prime is 121263556481. The reversal of 121263556461 is 164655362121.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 164655362121 = 3 ⋅54885120707.

It is a cyclic number.

It is not a de Polignac number, because 121263556461 - 2¹ = 121263556459 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121263556481) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20210592741 + ... + 20210592746.

It is an arithmetic number, because the mean of its divisors is an integer number (40421185488).

Almost surely, 2^121263556461 is an apocalyptic number.

It is an amenable number.

121263556461 is a deficient number, since it is larger than the sum of its proper divisors (40421185491).

121263556461 is an equidigital number, since it uses as much as digits as its factorization.

121263556461 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40421185490.

The product of its digits is 259200, while the sum is 42.

The spelling of 121263556461 in words is "one hundred twenty-one billion, two hundred sixty-three million, five hundred fifty-six thousand, four hundred sixty-one".