121751560621 has 4 divisors (see below), whose sum is σ = 124048759932. Its totient is φ = 119454361312.

The previous prime is 121751560583. The next prime is 121751560631. The reversal of 121751560621 is 126065157121.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 34108918596 + 87642642025 = 184686^2 + 296045^2 .

It is a cyclic number.

It is not a de Polignac number, because 121751560621 - 2²³ = 121743172013 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121751560631) 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, 1148599576 + ... + 1148599681.

It is an arithmetic number, because the mean of its divisors is an integer number (31012189983).

Almost surely, 2^121751560621 is an apocalyptic number.

It is an amenable number.

121751560621 is a deficient number, since it is larger than the sum of its proper divisors (2297199311).

121751560621 is an equidigital number, since it uses as much as digits as its factorization.

121751560621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2297199310.

The product of its (nonzero) digits is 25200, while the sum is 37.

The spelling of 121751560621 in words is "one hundred twenty-one billion, seven hundred fifty-one million, five hundred sixty thousand, six hundred twenty-one".