121566623 has 4 divisors (see below), whose sum is σ = 121729248. Its totient is φ = 121404000.

The previous prime is 121566619. The next prime is 121566631. The reversal of 121566623 is 326665121.

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

It is a cyclic number.

It is not a de Polignac number, because 121566623 - 2² = 121566619 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 121566623.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121566923) 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, 80186 + ... + 81687.

It is an arithmetic number, because the mean of its divisors is an integer number (30432312).

Almost surely, 2^121566623 is an apocalyptic number.

121566623 is a deficient number, since it is larger than the sum of its proper divisors (162625).

121566623 is an equidigital number, since it uses as much as digits as its factorization.

121566623 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 162624.

The product of its digits is 12960, while the sum is 32.

The square root of 121566623 is about 11025.7255090085. The cubic root of 121566623 is about 495.3795993107.

The spelling of 121566623 in words is "one hundred twenty-one million, five hundred sixty-six thousand, six hundred twenty-three".