91380019 has 2 divisors, whose sum is σ = 91380020. Its totient is φ = 91380018.

The previous prime is 91380017. The next prime is 91380059. The reversal of 91380019 is 91008319.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 91380019 - 2¹ = 91380017 is a prime.

It is a super-2 number, since 2×91380019² = 16700615744880722, which contains 22 as substring.

Together with 91380017, it forms a pair of twin primes.

It is equal to p_5292463 and since 91380019 and 5292463 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (91380017) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45690009 + 45690010.

It is an arithmetic number, because the mean of its divisors is an integer number (45690010).

Almost surely, 2^91380019 is an apocalyptic number.

91380019 is a deficient number, since it is larger than the sum of its proper divisors (1).

91380019 is an equidigital number, since it uses as much as digits as its factorization.

91380019 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1944, while the sum is 31.

The square root of 91380019 is about 9559.2896702632. The cubic root of 91380019 is about 450.4193933723.

The spelling of 91380019 in words is "ninety-one million, three hundred eighty thousand, nineteen".