90691823 has 2 divisors, whose sum is σ = 90691824. Its totient is φ = 90691822.

The previous prime is 90691819. The next prime is 90691831. The reversal of 90691823 is 32819609.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 90691823 - 2² = 90691819 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (90691873) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45345911 + 45345912.

It is an arithmetic number, because the mean of its divisors is an integer number (45345912).

Almost surely, 2^90691823 is an apocalyptic number.

90691823 is a deficient number, since it is larger than the sum of its proper divisors (1).

90691823 is an equidigital number, since it uses as much as digits as its factorization.

90691823 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 23328, while the sum is 38.

The square root of 90691823 is about 9523.2254514949. The cubic root of 90691823 is about 449.2858185842.

It can be divided in two parts, 906 and 91823, that added together give a palindrome (92729).

The spelling of 90691823 in words is "ninety million, six hundred ninety-one thousand, eight hundred twenty-three".