90424991 has 4 divisors (see below), whose sum is σ = 91023984. Its totient is φ = 89826000.

The previous prime is 90424981. The next prime is 90425011. The reversal of 90424991 is 19942409.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19942409 = 71 ⋅280879.

It is a cyclic number.

It is not a de Polignac number, because 90424991 - 2⁶ = 90424927 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90424981) 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, 299270 + ... + 299571.

It is an arithmetic number, because the mean of its divisors is an integer number (22755996).

Almost surely, 2^90424991 is an apocalyptic number.

90424991 is a deficient number, since it is larger than the sum of its proper divisors (598993).

90424991 is a wasteful number, since it uses less digits than its factorization.

90424991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 598992.

The product of its (nonzero) digits is 23328, while the sum is 38.

The square root of 90424991 is about 9509.2055924772. The cubic root of 90424991 is about 448.8447586093.

The spelling of 90424991 in words is "ninety million, four hundred twenty-four thousand, nine hundred ninety-one".