90781937 has 2 divisors, whose sum is σ = 90781938. Its totient is φ = 90781936.

The previous prime is 90781927. The next prime is 90781939. The reversal of 90781937 is 73918709.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 90649441 + 132496 = 9521^2 + 364^2 .

It is a cyclic number.

It is not a de Polignac number, because 90781937 - 2⁸ = 90781681 is a prime.

Together with 90781939, 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 (90781939) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45390968 + 45390969.

It is an arithmetic number, because the mean of its divisors is an integer number (45390969).

Almost surely, 2^90781937 is an apocalyptic number.

It is an amenable number.

90781937 is a deficient number, since it is larger than the sum of its proper divisors (1).

90781937 is an equidigital number, since it uses as much as digits as its factorization.

90781937 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 95256, while the sum is 44.

The square root of 90781937 is about 9527.9555519534. The cubic root of 90781937 is about 449.4345770891.

The spelling of 90781937 in words is "ninety million, seven hundred eighty-one thousand, nine hundred thirty-seven".