90861438529 has 4 divisors (see below), whose sum is σ = 90864176260. Its totient is φ = 90858700800.

The previous prime is 90861438509. The next prime is 90861438539. The reversal of 90861438529 is 92583416809.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 35391768129 + 55469670400 = 188127^2 + 235520^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-90861438529 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 90861438529.

It is not an unprimeable number, because it can be changed into a prime (90861438509) 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, 1318464 + ... + 1385665.

It is an arithmetic number, because the mean of its divisors is an integer number (22716044065).

Almost surely, 2^90861438529 is an apocalyptic number.

It is an amenable number.

90861438529 is a deficient number, since it is larger than the sum of its proper divisors (2737731).

90861438529 is a wasteful number, since it uses less digits than its factorization.

90861438529 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2737730.

The product of its (nonzero) digits is 3732480, while the sum is 55.

The spelling of 90861438529 in words is "ninety billion, eight hundred sixty-one million, four hundred thirty-eight thousand, five hundred twenty-nine".