90521551 has 2 divisors, whose sum is σ = 90521552. Its totient is φ = 90521550.

The previous prime is 90521507. The next prime is 90521603. The reversal of 90521551 is 15512509.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 90521551 - 2⁷ = 90521423 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (90521051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45260775 + 45260776.

It is an arithmetic number, because the mean of its divisors is an integer number (45260776).

Almost surely, 2^90521551 is an apocalyptic number.

90521551 is a deficient number, since it is larger than the sum of its proper divisors (1).

90521551 is an equidigital number, since it uses as much as digits as its factorization.

90521551 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2250, while the sum is 28.

The square root of 90521551 is about 9514.2814232080. The cubic root of 90521551 is about 449.0044675260.

The spelling of 90521551 in words is "ninety million, five hundred twenty-one thousand, five hundred fifty-one".