123487491 has 4 divisors (see below), whose sum is σ = 164649992. Its totient is φ = 82324992.

The previous prime is 123487451. The next prime is 123487501. The reversal of 123487491 is 194784321.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 194784321 = 3 ⋅64928107.

It is not a de Polignac number, because 123487491 - 2¹⁷ = 123356419 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (123487451) 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, 20581246 + ... + 20581251.

It is an arithmetic number, because the mean of its divisors is an integer number (41162498).

Almost surely, 2^123487491 is an apocalyptic number.

123487491 is a deficient number, since it is larger than the sum of its proper divisors (41162501).

123487491 is an equidigital number, since it uses as much as digits as its factorization.

123487491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41162500.

The product of its digits is 48384, while the sum is 39.

The square root of 123487491 is about 11112.4925646769. The cubic root of 123487491 is about 497.9751322238.

The spelling of 123487491 in words is "one hundred twenty-three million, four hundred eighty-seven thousand, four hundred ninety-one".