42249991 has 16 divisors (see below), whose sum is σ = 49550400. Its totient is φ = 35278848.

The previous prime is 42249973. The next prime is 42249997. The reversal of 42249991 is 19994224.

It is a cyclic number.

It is not a de Polignac number, because 42249991 - 2⁹ = 42249479 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42249997) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 45015 + ... + 45943.

It is an arithmetic number, because the mean of its divisors is an integer number (3096900).

Almost surely, 2^42249991 is an apocalyptic number.

42249991 is a deficient number, since it is larger than the sum of its proper divisors (7300409).

42249991 is an equidigital number, since it uses as much as digits as its factorization.

42249991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1098.

The product of its digits is 46656, while the sum is 40.

The square root of 42249991 is about 6499.9993076923. Note that the first 3 decimals coincide. The cubic root of 42249991 is about 348.2909636634.

The spelling of 42249991 in words is "forty-two million, two hundred forty-nine thousand, nine hundred ninety-one".