91723501 has 2 divisors, whose sum is σ = 91723502. Its totient is φ = 91723500.

The previous prime is 91723493. The next prime is 91723529. The reversal of 91723501 is 10532719.

It is an a-pointer prime, because the next prime (91723529) can be obtained adding 91723501 to its sum of digits (28).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 89965225 + 1758276 = 9485^2 + 1326^2 .

It is an emirp because it is prime and its reverse (10532719) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 91723501 - 2³ = 91723493 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 91723501.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91723561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45861750 + 45861751.

It is an arithmetic number, because the mean of its divisors is an integer number (45861751).

Almost surely, 2^91723501 is an apocalyptic number.

It is an amenable number.

91723501 is a deficient number, since it is larger than the sum of its proper divisors (1).

91723501 is an equidigital number, since it uses as much as digits as its factorization.

91723501 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1890, while the sum is 28.

The square root of 91723501 is about 9577.2386939034. The cubic root of 91723501 is about 450.9830377935.

The spelling of 91723501 in words is "ninety-one million, seven hundred twenty-three thousand, five hundred one".