91407973 has 2 divisors, whose sum is σ = 91407974. Its totient is φ = 91407972.

The previous prime is 91407959. The next prime is 91408007. The reversal of 91407973 is 37970419.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 75742209 + 15665764 = 8703^2 + 3958^2 .

It is a cyclic number.

It is not a de Polignac number, because 91407973 - 2²¹ = 89310821 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91207973) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45703986 + 45703987.

It is an arithmetic number, because the mean of its divisors is an integer number (45703987).

Almost surely, 2^91407973 is an apocalyptic number.

It is an amenable number.

91407973 is a deficient number, since it is larger than the sum of its proper divisors (1).

91407973 is an equidigital number, since it uses as much as digits as its factorization.

91407973 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 47628, while the sum is 40.

The square root of 91407973 is about 9560.7516963887. The cubic root of 91407973 is about 450.4653178540.

The spelling of 91407973 in words is "ninety-one million, four hundred seven thousand, nine hundred seventy-three".