42999021 has 24 divisors (see below), whose sum is σ = 67223520. Its totient is φ = 26328096.

The previous prime is 42999017. The next prime is 42999041. The reversal of 42999021 is 12099924.

It is not a de Polignac number, because 42999021 - 2² = 42999017 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42999041) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 25750 + ... + 27368.

It is an arithmetic number, because the mean of its divisors is an integer number (2800980).

Almost surely, 2^42999021 is an apocalyptic number.

It is an amenable number.

42999021 is a deficient number, since it is larger than the sum of its proper divisors (24224499).

42999021 is a wasteful number, since it uses less digits than its factorization.

42999021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1865 (or 1862 counting only the distinct ones).

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

The square root of 42999021 is about 6557.3638758269. The cubic root of 42999021 is about 350.3371472381.

The spelling of 42999021 in words is "forty-two million, nine hundred ninety-nine thousand, twenty-one".