90690661 has 2 divisors, whose sum is σ = 90690662. Its totient is φ = 90690660.

The previous prime is 90690659. The next prime is 90690703. The reversal of 90690661 is 16609609.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 60933636 + 29757025 = 7806^2 + 5455^2 .

It is a cyclic number.

It is not a de Polignac number, because 90690661 - 2¹ = 90690659 is a prime.

Together with 90690659, it forms a pair of twin primes.

It is equal to p_5254759 and since 90690661 and 5254759 have the same sum of digits, it is a Honaker prime.

It is a self number, because there is not a number n which added to its sum of digits gives 90690661.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (90691661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45345330 + 45345331.

It is an arithmetic number, because the mean of its divisors is an integer number (45345331).

Almost surely, 2^90690661 is an apocalyptic number.

It is an amenable number.

90690661 is a deficient number, since it is larger than the sum of its proper divisors (1).

90690661 is an equidigital number, since it uses as much as digits as its factorization.

90690661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 17496, while the sum is 37.

The square root of 90690661 is about 9523.1644425579. The cubic root of 90690661 is about 449.2838997329.

The spelling of 90690661 in words is "ninety million, six hundred ninety thousand, six hundred sixty-one".