428220131 has 4 divisors (see below), whose sum is σ = 432377712. Its totient is φ = 424062552.

The previous prime is 428220109. The next prime is 428220139. The reversal of 428220131 is 131022824.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 428220131 - 2²² = 424025827 is a prime.

It is a super-2 number, since 2×428220131² = 366744961187314322, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 428220097 and 428220106.

It is not an unprimeable number, because it can be changed into a prime (428220139) 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, 2078636 + ... + 2078841.

It is an arithmetic number, because the mean of its divisors is an integer number (108094428).

Almost surely, 2^428220131 is an apocalyptic number.

428220131 is a deficient number, since it is larger than the sum of its proper divisors (4157581).

428220131 is a wasteful number, since it uses less digits than its factorization.

428220131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4157580.

The product of its (nonzero) digits is 768, while the sum is 23.

The square root of 428220131 is about 20693.4803984250. The cubic root of 428220131 is about 753.7413826689.

Adding to 428220131 its reverse (131022824), we get a palindrome (559242955).

The spelling of 428220131 in words is "four hundred twenty-eight million, two hundred twenty thousand, one hundred thirty-one".