91621037 has 2 divisors, whose sum is σ = 91621038. Its totient is φ = 91621036.

The previous prime is 91621009. The next prime is 91621069. The reversal of 91621037 is 73012619.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 83521321 + 8099716 = 9139^2 + 2846^2 .

It is an emirp because it is prime and its reverse (73012619) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 91621037 - 2¹⁸ = 91358893 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91621087) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45810518 + 45810519.

It is an arithmetic number, because the mean of its divisors is an integer number (45810519).

Almost surely, 2^91621037 is an apocalyptic number.

It is an amenable number.

91621037 is a deficient number, since it is larger than the sum of its proper divisors (1).

91621037 is an equidigital number, since it uses as much as digits as its factorization.

91621037 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2268, while the sum is 29.

The square root of 91621037 is about 9571.8878493221. The cubic root of 91621037 is about 450.8150447020.

The spelling of 91621037 in words is "ninety-one million, six hundred twenty-one thousand, thirty-seven".