426666021 has 4 divisors (see below), whose sum is σ = 568888032. Its totient is φ = 284444012.

The previous prime is 426666007. The next prime is 426666041. The reversal of 426666021 is 120666624.

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 426666021 - 2¹⁴ = 426649637 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (426666041) 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, 71111001 + ... + 71111006.

It is an arithmetic number, because the mean of its divisors is an integer number (142222008).

Almost surely, 2^426666021 is an apocalyptic number.

It is an amenable number.

426666021 is a deficient number, since it is larger than the sum of its proper divisors (142222011).

426666021 is a wasteful number, since it uses less digits than its factorization.

426666021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 142222010.

The product of its (nonzero) digits is 20736, while the sum is 33.

The square root of 426666021 is about 20655.8955506654. The cubic root of 426666021 is about 752.8284433574.

The spelling of 426666021 in words is "four hundred twenty-six million, six hundred sixty-six thousand, twenty-one".