90909001 has 4 divisors (see below), whose sum is σ = 90953604. Its totient is φ = 90864400.

The previous prime is 90908959. The next prime is 90909031. The reversal of 90909001 is 10090909.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 10090909 = 89 ⋅113381.

It can be written as a sum of positive squares in 2 ways, for example, as 89321401 + 1587600 = 9451^2 + 1260^2 .

It is a cyclic number.

It is not a de Polignac number, because 90909001 - 2¹¹ = 90906953 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (90909031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19090 + ... + 23371.

It is an arithmetic number, because the mean of its divisors is an integer number (22738401).

Almost surely, 2^90909001 is an apocalyptic number.

It is an amenable number.

90909001 is a deficient number, since it is larger than the sum of its proper divisors (44603).

90909001 is a wasteful number, since it uses less digits than its factorization.

90909001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44602.

The product of its (nonzero) digits is 729, while the sum is 28.

The square root of 90909001 is about 9534.6211775823. The cubic root of 90909001 is about 449.6441647898.

The spelling of 90909001 in words is "ninety million, nine hundred nine thousand, one".