91913641 has 4 divisors (see below), whose sum is σ = 93420484. Its totient is φ = 90406800.

The previous prime is 91913639. The next prime is 91913671. The reversal of 91913641 is 14631919.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 14631919 = 19 ⋅770101.

It can be written as a sum of positive squares in 2 ways, for example, as 36723600 + 55190041 = 6060^2 + 7429^2 .

It is a cyclic number.

It is not a de Polignac number, because 91913641 - 2¹ = 91913639 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 91913597 and 91913606.

It is not an unprimeable number, because it can be changed into a prime (91913671) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 753330 + ... + 753451.

It is an arithmetic number, because the mean of its divisors is an integer number (23355121).

Almost surely, 2^91913641 is an apocalyptic number.

It is an amenable number.

91913641 is a deficient number, since it is larger than the sum of its proper divisors (1506843).

91913641 is a wasteful number, since it uses less digits than its factorization.

91913641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1506842.

The product of its digits is 5832, while the sum is 34.

The square root of 91913641 is about 9587.1602156217. The cubic root of 91913641 is about 451.2944473731.

The spelling of 91913641 in words is "ninety-one million, nine hundred thirteen thousand, six hundred forty-one".