28429631 has 4 divisors (see below), whose sum is σ = 28819152. Its totient is φ = 28040112.

The previous prime is 28429619. The next prime is 28429649. The reversal of 28429631 is 13692482.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13692482 = 2 ⋅6846241.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28429631 is a prime.

It is a super-2 number, since 2×28429631² = 1616487837592322, 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 = 28429591 and 28429600.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28429691) 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, 194651 + ... + 194796.

It is an arithmetic number, because the mean of its divisors is an integer number (7204788).

Almost surely, 2^28429631 is an apocalyptic number.

28429631 is a deficient number, since it is larger than the sum of its proper divisors (389521).

28429631 is an equidigital number, since it uses as much as digits as its factorization.

28429631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 389520.

The product of its digits is 20736, while the sum is 35.

The square root of 28429631 is about 5331.9443920581. The cubic root of 28429631 is about 305.2041310183.

The spelling of 28429631 in words is "twenty-eight million, four hundred twenty-nine thousand, six hundred thirty-one".