28696421 has 12 divisors (see below), whose sum is σ = 31946796. Its totient is φ = 25623360.

The previous prime is 28696417. The next prime is 28696439. The reversal of 28696421 is 12469682.

It can be written as a sum of positive squares in 2 ways, for example, as 8491396 + 20205025 = 2914^2 + 4495^2 .

It is not a de Polignac number, because 28696421 - 2² = 28696417 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28696121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 11345 + ... + 13641.

It is an arithmetic number, because the mean of its divisors is an integer number (2662233).

Almost surely, 2^28696421 is an apocalyptic number.

It is an amenable number.

28696421 is a deficient number, since it is larger than the sum of its proper divisors (3250375).

28696421 is a wasteful number, since it uses less digits than its factorization.

28696421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2372 (or 2341 counting only the distinct ones).

The product of its digits is 41472, while the sum is 38.

The square root of 28696421 is about 5356.9040499154. The cubic root of 28696421 is about 306.1558613335.

The spelling of 28696421 in words is "twenty-eight million, six hundred ninety-six thousand, four hundred twenty-one".