91215463639 has 2 divisors, whose sum is σ = 91215463640. Its totient is φ = 91215463638.

The previous prime is 91215463571. The next prime is 91215463643. The reversal of 91215463639 is 93636451219.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 91215463639 - 2¹¹ = 91215461591 is a prime.

It is a super-2 number, since 2×91215463639² (a number of 23 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 91215463592 and 91215463601.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91215463699) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45607731819 + 45607731820.

It is an arithmetic number, because the mean of its divisors is an integer number (45607731820).

Almost surely, 2^91215463639 is an apocalyptic number.

91215463639 is a deficient number, since it is larger than the sum of its proper divisors (1).

91215463639 is an equidigital number, since it uses as much as digits as its factorization.

91215463639 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1049760, while the sum is 49.

The spelling of 91215463639 in words is "ninety-one billion, two hundred fifteen million, four hundred sixty-three thousand, six hundred thirty-nine".