90720001 has 4 divisors (see below), whose sum is σ = 90922500. Its totient is φ = 90517504.

The previous prime is 90719987. The next prime is 90720023. The reversal of 90720001 is 10002709.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 10002709 = 29 ⋅344921.

It can be written as a sum of positive squares in 2 ways, for example, as 36917776 + 53802225 = 6076^2 + 7335^2 .

It is a cyclic number.

It is not a de Polignac number, because 90720001 - 2⁵ = 90719969 is a prime.

It is not an unprimeable number, because it can be changed into a prime (90720101) 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, 100576 + ... + 101473.

It is an arithmetic number, because the mean of its divisors is an integer number (22730625).

Almost surely, 2^90720001 is an apocalyptic number.

It is an amenable number.

90720001 is a deficient number, since it is larger than the sum of its proper divisors (202499).

90720001 is a wasteful number, since it uses less digits than its factorization.

90720001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 202498.

The product of its (nonzero) digits is 126, while the sum is 19.

The square root of 90720001 is about 9524.7047723276. The cubic root of 90720001 is about 449.3323448841.

The spelling of 90720001 in words is "ninety million, seven hundred twenty thousand, one".