90023642 has 4 divisors (see below), whose sum is σ = 135035466. Its totient is φ = 45011820.

The previous prime is 90023641. The next prime is 90023651. The reversal of 90023642 is 24632009.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 24632009 = 2339 ⋅10531.

It can be written as a sum of positive squares in only one way, i.e., 77070841 + 12952801 = 8779^2 + 3599^2 .

It is a super-2 number, since 2×90023642² = 16208512237888328, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (90023641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 22505909 + ... + 22505912.

Almost surely, 2^90023642 is an apocalyptic number.

90023642 is a deficient number, since it is larger than the sum of its proper divisors (45011824).

90023642 is a wasteful number, since it uses less digits than its factorization.

90023642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45011823.

The product of its (nonzero) digits is 2592, while the sum is 26.

The square root of 90023642 is about 9488.0789414928. The cubic root of 90023642 is about 448.1797117280.

It can be divided in two parts, 900 and 23642, that added together give a palindrome (24542).

The spelling of 90023642 in words is "ninety million, twenty-three thousand, six hundred forty-two".