42766021 has 4 divisors (see below), whose sum is σ = 42905632. Its totient is φ = 42626412.

The previous prime is 42766007. The next prime is 42766027. The reversal of 42766021 is 12066724.

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 42766021 - 2⁷ = 42765893 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 (42766027) 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, 69345 + ... + 69958.

It is an arithmetic number, because the mean of its divisors is an integer number (10726408).

Almost surely, 2^42766021 is an apocalyptic number.

It is an amenable number.

42766021 is a deficient number, since it is larger than the sum of its proper divisors (139611).

42766021 is a wasteful number, since it uses less digits than its factorization.

42766021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139610.

The product of its (nonzero) digits is 4032, while the sum is 28.

The square root of 42766021 is about 6539.5734570383. The cubic root of 42766021 is about 349.7032068998.

The spelling of 42766021 in words is "forty-two million, seven hundred sixty-six thousand, twenty-one".