91909242 has 80 divisors (see below), whose sum is σ = 227696832. Its totient is φ = 27561600.

The previous prime is 91909241. The next prime is 91909267. The reversal of 91909242 is 24290919.

It is a junction number, because it is equal to n+sod(n) for n = 91909197 and 91909206.

It is not an unprimeable number, because it can be changed into a prime (91909241) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 62617 + ... + 64067.

Almost surely, 2^91909242 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 91909242, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (113848416).

91909242 is an abundant number, since it is smaller than the sum of its proper divisors (135787590).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

91909242 is a wasteful number, since it uses less digits than its factorization.

91909242 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1505 (or 1496 counting only the distinct ones).

The product of its (nonzero) digits is 11664, while the sum is 36.

The square root of 91909242 is about 9586.9307914473. The cubic root of 91909242 is about 451.2872475859.

The spelling of 91909242 in words is "ninety-one million, nine hundred nine thousand, two hundred forty-two".