402666217 has 4 divisors (see below), whose sum is σ = 402938496. Its totient is φ = 402393940.

The previous prime is 402666211. The next prime is 402666241. The reversal of 402666217 is 712666204.

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 402666217 - 2¹⁵ = 402633449 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (402666211) 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, 133909 + ... + 136882.

It is an arithmetic number, because the mean of its divisors is an integer number (100734624).

Almost surely, 2^402666217 is an apocalyptic number.

It is an amenable number.

402666217 is a deficient number, since it is larger than the sum of its proper divisors (272279).

402666217 is a wasteful number, since it uses less digits than its factorization.

402666217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 272278.

The product of its (nonzero) digits is 24192, while the sum is 34.

The square root of 402666217 is about 20066.5447200060. The cubic root of 402666217 is about 738.4397470502.

The spelling of 402666217 in words is "four hundred two million, six hundred sixty-six thousand, two hundred seventeen".