30428639 has 4 divisors (see below), whose sum is σ = 31410240. Its totient is φ = 29447040.

The previous prime is 30428621. The next prime is 30428687. The reversal of 30428639 is 93682403.

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 30428639 - 2⁸ = 30428383 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 30428599 and 30428608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (30428039) 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, 490754 + ... + 490815.

It is an arithmetic number, because the mean of its divisors is an integer number (7852560).

Almost surely, 2^30428639 is an apocalyptic number.

30428639 is a deficient number, since it is larger than the sum of its proper divisors (981601).

30428639 is an equidigital number, since it uses as much as digits as its factorization.

30428639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 981600.

The product of its (nonzero) digits is 31104, while the sum is 35.

The square root of 30428639 is about 5516.2160037475. The cubic root of 30428639 is about 312.1961257291.

The spelling of 30428639 in words is "thirty million, four hundred twenty-eight thousand, six hundred thirty-nine".