406820689 has 4 divisors (see below), whose sum is σ = 443804400. Its totient is φ = 369836980.

The previous prime is 406820677. The next prime is 406820747. The reversal of 406820689 is 986028604.

It is a happy number.

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 406820689 - 2⁹ = 406820177 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (406820629) 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, 18491839 + ... + 18491860.

It is an arithmetic number, because the mean of its divisors is an integer number (110951100).

Almost surely, 2^406820689 is an apocalyptic number.

It is an amenable number.

406820689 is a deficient number, since it is larger than the sum of its proper divisors (36983711).

406820689 is a wasteful number, since it uses less digits than its factorization.

406820689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36983710.

The product of its (nonzero) digits is 165888, while the sum is 43.

The square root of 406820689 is about 20169.7964541043. The cubic root of 406820689 is about 740.9706576905.

The spelling of 406820689 in words is "four hundred six million, eight hundred twenty thousand, six hundred eighty-nine".