90901001 has 2 divisors, whose sum is σ = 90901002. Its totient is φ = 90901000.

The previous prime is 90900983. The next prime is 90901003. The reversal of 90901001 is 10010909.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 58125376 + 32775625 = 7624^2 + 5725^2 .

It is a cyclic number.

It is not a de Polignac number, because 90901001 - 2⁶ = 90900937 is a prime.

Together with 90901003, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (90901003) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45450500 + 45450501.

It is an arithmetic number, because the mean of its divisors is an integer number (45450501).

Almost surely, 2^90901001 is an apocalyptic number.

It is an amenable number.

90901001 is a deficient number, since it is larger than the sum of its proper divisors (1).

90901001 is an equidigital number, since it uses as much as digits as its factorization.

90901001 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 81, while the sum is 20.

The square root of 90901001 is about 9534.2016446056. The cubic root of 90901001 is about 449.6309748277.

The spelling of 90901001 in words is "ninety million, nine hundred one thousand, one".