42521866 has 8 divisors (see below), whose sum is σ = 63811044. Its totient is φ = 21251520.

The previous prime is 42521861. The next prime is 42521903. The reversal of 42521866 is 66812524.

It can be written as a sum of positive squares in 2 ways, for example, as 41873841 + 648025 = 6471^2 + 805^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (42521861) 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, 4696 + ... + 10348.

Almost surely, 2^42521866 is an apocalyptic number.

42521866 is a deficient number, since it is larger than the sum of its proper divisors (21289178).

42521866 is a wasteful number, since it uses less digits than its factorization.

42521866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9416.

The product of its digits is 23040, while the sum is 34.

The square root of 42521866 is about 6520.8792351952. The cubic root of 42521866 is about 349.0364408875.

The spelling of 42521866 in words is "forty-two million, five hundred twenty-one thousand, eight hundred sixty-six".