123540869 has 4 divisors (see below), whose sum is σ = 130043040. Its totient is φ = 117038700.

The previous prime is 123540829. The next prime is 123540881. The reversal of 123540869 is 968045321.

It is a happy number.

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: 968045321 = 23 ⋅42088927.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-123540869 is a prime.

It is a super-2 number, since 2×123540869² = 30524692626550322, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123540829) 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, 3251057 + ... + 3251094.

It is an arithmetic number, because the mean of its divisors is an integer number (32510760).

Almost surely, 2^123540869 is an apocalyptic number.

123540869 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

123540869 is a deficient number, since it is larger than the sum of its proper divisors (6502171).

123540869 is an equidigital number, since it uses as much as digits as its factorization.

123540869 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6502170.

The product of its (nonzero) digits is 51840, while the sum is 38.

The square root of 123540869 is about 11114.8940165887. The cubic root of 123540869 is about 498.0468725202.

The spelling of 123540869 in words is "one hundred twenty-three million, five hundred forty thousand, eight hundred sixty-nine".