90235987 has 2 divisors, whose sum is σ = 90235988. Its totient is φ = 90235986.

The previous prime is 90235961. The next prime is 90235991. The reversal of 90235987 is 78953209.

It is a happy number.

It is a strong prime.

It is an emirp because it is prime and its reverse (78953209) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 90235987 - 2¹⁵ = 90203219 is a prime.

It is not a weakly prime, because it can be changed into another prime (90235927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45117993 + 45117994.

It is an arithmetic number, because the mean of its divisors is an integer number (45117994).

Almost surely, 2^90235987 is an apocalyptic number.

90235987 is a deficient number, since it is larger than the sum of its proper divisors (1).

90235987 is an equidigital number, since it uses as much as digits as its factorization.

90235987 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 136080, while the sum is 43.

The square root of 90235987 is about 9499.2624450533. The cubic root of 90235987 is about 448.5318192028.

The spelling of 90235987 in words is "ninety million, two hundred thirty-five thousand, nine hundred eighty-seven".