90435515881 has 4 divisors (see below), whose sum is σ = 90436594564. Its totient is φ = 90434437200.

The previous prime is 90435515761. The next prime is 90435515897. The reversal of 90435515881 is 18851553409.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 18851553409 = 13 ⋅1450119493.

It can be written as a sum of positive squares in 2 ways, for example, as 40624418025 + 49811097856 = 201555^2 + 223184^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-90435515881 is a prime.

It is a super-2 number, since 2×90435515881² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (90435510881) 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, 401910 + ... + 585151.

It is an arithmetic number, because the mean of its divisors is an integer number (22609148641).

Almost surely, 2^90435515881 is an apocalyptic number.

It is an amenable number.

90435515881 is a deficient number, since it is larger than the sum of its proper divisors (1078683).

90435515881 is an equidigital number, since it uses as much as digits as its factorization.

90435515881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1078682.

The product of its (nonzero) digits is 864000, while the sum is 49.

The spelling of 90435515881 in words is "ninety billion, four hundred thirty-five million, five hundred fifteen thousand, eight hundred eighty-one".