42090215281 has 9 divisors (see below), whose sum is σ = 42349268619. Its totient is φ = 41832740736.

The previous prime is 42090215231. The next prime is 42090215327. The reversal of 42090215281 is 18251209024.

The square root of 42090215281 is 205159.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 10197970225 + 31892245056 = 100985^2 + 178584^2 .

It is not a de Polignac number, because 42090215281 - 2²¹ = 42088118129 is a prime.

It is a super-2 number, since 2×42090215281² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42090215231) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 39595156 + ... + 39596218.

It is an arithmetic number, because the mean of its divisors is an integer number (4705474291).

Almost surely, 2^42090215281 is an apocalyptic number.

42090215281 is the 205159-th square number.

42090215281 is the 102580-th centered octagonal number.

It is an amenable number.

42090215281 is a deficient number, since it is larger than the sum of its proper divisors (259053338).

42090215281 is an frugal number, since it uses more digits than its factorization.

42090215281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2512 (or 1256 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 34.

The spelling of 42090215281 in words is "forty-two billion, ninety million, two hundred fifteen thousand, two hundred eighty-one".