90409409 has 2 divisors, whose sum is σ = 90409410. Its totient is φ = 90409408.

The previous prime is 90409369. The next prime is 90409433. The reversal of 90409409 is 90490409.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 90307009 + 102400 = 9503^2 + 320^2 .

It is a cyclic number.

It is not a de Polignac number, because 90409409 - 2¹² = 90405313 is a prime.

It is a super-2 number, since 2×90409409² = 16347722471458562, which contains 22 as substring.

It is a Chen prime.

It is equal to p_5239439 and since 90409409 and 5239439 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (90409439) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45204704 + 45204705.

It is an arithmetic number, because the mean of its divisors is an integer number (45204705).

Almost surely, 2^90409409 is an apocalyptic number.

It is an amenable number.

90409409 is a deficient number, since it is larger than the sum of its proper divisors (1).

90409409 is an equidigital number, since it uses as much as digits as its factorization.

90409409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11664, while the sum is 35.

The square root of 90409409 is about 9508.3862458358. The cubic root of 90409409 is about 448.8189755423.

The spelling of 90409409 in words is "ninety million, four hundred nine thousand, four hundred nine".