123259921010821 has 16 divisors (see below), whose sum is σ = 142751083305600. Its totient is φ = 104242719817728.

The previous prime is 123259921010819. The next prime is 123259921010869. The reversal of 123259921010821 is 128010129952321.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 123259921010821 - 2¹ = 123259921010819 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123259921010221) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 137492956 + ... + 138386533.

It is an arithmetic number, because the mean of its divisors is an integer number (8921942706600).

Almost surely, 2^{123259921010821} is an apocalyptic number.

It is an amenable number.

123259921010821 is a deficient number, since it is larger than the sum of its proper divisors (19491162294779).

123259921010821 is an equidigital number, since it uses as much as digits as its factorization.

123259921010821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 275880348.

The product of its (nonzero) digits is 155520, while the sum is 46.

The spelling of 123259921010821 in words is "one hundred twenty-three trillion, two hundred fifty-nine billion, nine hundred twenty-one million, ten thousand, eight hundred twenty-one".