123409881 has 45 divisors (see below), whose sum is σ = 216787701. Its totient is φ = 67453848.

The previous prime is 123409849. The next prime is 123409901. The reversal of 123409881 is 188904321.

The square root of 123409881 is 11109.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 123409881 - 2⁵ = 123409849 is a prime.

It is a super-3 number, since 3×123409881³ (a number of 25 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not an unprimeable number, because it can be changed into a prime (123409831) by changing a digit.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 5365636 + ... + 5365658.

Almost surely, 2^123409881 is an apocalyptic number.

123409881 is the 11109-th square number.

123409881 is the 5555-th centered octagonal number.

It is an amenable number.

123409881 is a deficient number, since it is larger than the sum of its proper divisors (93377820).

123409881 is an frugal number, since it uses more digits than its factorization.

123409881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 112 (or 33 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 36.

The cubic root of 123409881 is about 497.8707871088.

Multiplying 123409881 by its sum of digits (36), we get a square (4442755716 = 66654²).

The spelling of 123409881 in words is "one hundred twenty-three million, four hundred nine thousand, eight hundred eighty-one".