90154991 has 2 divisors, whose sum is σ = 90154992. Its totient is φ = 90154990.

The previous prime is 90154979. The next prime is 90154993. The reversal of 90154991 is 19945109.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-90154991 is a prime.

Together with 90154993, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (90154993) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45077495 + 45077496.

It is an arithmetic number, because the mean of its divisors is an integer number (45077496).

Almost surely, 2^90154991 is an apocalyptic number.

90154991 is a deficient number, since it is larger than the sum of its proper divisors (1).

90154991 is an equidigital number, since it uses as much as digits as its factorization.

90154991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 14580, while the sum is 38.

The square root of 90154991 is about 9494.9982095838. The cubic root of 90154991 is about 448.3975780144.

The spelling of 90154991 in words is "ninety million, one hundred fifty-four thousand, nine hundred ninety-one".