90437609 has 2 divisors, whose sum is σ = 90437610. Its totient is φ = 90437608.

The previous prime is 90437579. The next prime is 90437621. The reversal of 90437609 is 90673409.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 51437584 + 39000025 = 7172^2 + 6245^2 .

It is an emirp because it is prime and its reverse (90673409) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-90437609 is a prime.

It is a super-2 number, since 2×90437609² = 16357922243273762, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (90437639) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45218804 + 45218805.

It is an arithmetic number, because the mean of its divisors is an integer number (45218805).

Almost surely, 2^90437609 is an apocalyptic number.

It is an amenable number.

90437609 is a deficient number, since it is larger than the sum of its proper divisors (1).

90437609 is an equidigital number, since it uses as much as digits as its factorization.

90437609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 40824, while the sum is 38.

The square root of 90437609 is about 9509.8690316954. The cubic root of 90437609 is about 448.8656350643.

The spelling of 90437609 in words is "ninety million, four hundred thirty-seven thousand, six hundred nine".