91861049 has 4 divisors (see below), whose sum is σ = 104984064. Its totient is φ = 78738036.

The previous prime is 91861043. The next prime is 91861051. The reversal of 91861049 is 94016819.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 91861049 - 2⁸ = 91860793 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91861043) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6561497 + ... + 6561510.

It is an arithmetic number, because the mean of its divisors is an integer number (26246016).

Almost surely, 2^91861049 is an apocalyptic number.

It is an amenable number.

91861049 is a deficient number, since it is larger than the sum of its proper divisors (13123015).

91861049 is a wasteful number, since it uses less digits than its factorization.

91861049 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13123014.

The product of its (nonzero) digits is 15552, while the sum is 38.

The square root of 91861049 is about 9584.4169880071. The cubic root of 91861049 is about 451.2083556692.

The spelling of 91861049 in words is "ninety-one million, eight hundred sixty-one thousand, forty-nine".