90781123 has 4 divisors (see below), whose sum is σ = 91680048. Its totient is φ = 89882200.

The previous prime is 90781109. The next prime is 90781147. The reversal of 90781123 is 32118709.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 32118709 = 7 ⋅4588387.

It is a cyclic number.

It is not a de Polignac number, because 90781123 - 2¹³ = 90772931 is a prime.

It is a super-2 number, since 2×90781123² = 16482424586282258, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (90781193) 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, 449311 + ... + 449512.

It is an arithmetic number, because the mean of its divisors is an integer number (22920012).

Almost surely, 2^90781123 is an apocalyptic number.

90781123 is a deficient number, since it is larger than the sum of its proper divisors (898925).

90781123 is a wasteful number, since it uses less digits than its factorization.

90781123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 898924.

The product of its (nonzero) digits is 3024, while the sum is 31.

The square root of 90781123 is about 9527.9128354535. The cubic root of 90781123 is about 449.4332337938.

It can be divided in two parts, 9078 and 1123, that added together give a palindrome (10201).

The spelling of 90781123 in words is "ninety million, seven hundred eighty-one thousand, one hundred twenty-three".