28401231 has 8 divisors (see below), whose sum is σ = 37895040. Its totient is φ = 18920792.

The previous prime is 28401229. The next prime is 28401259. The reversal of 28401231 is 13210482.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 28401231 - 2¹ = 28401229 is a prime.

It is a super-2 number, since 2×28401231² = 1613259844630722, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 28401198 and 28401207.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28401221) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3796 + ... + 8438.

It is an arithmetic number, because the mean of its divisors is an integer number (4736880).

Almost surely, 2^28401231 is an apocalyptic number.

28401231 is a deficient number, since it is larger than the sum of its proper divisors (9493809).

28401231 is a wasteful number, since it uses less digits than its factorization.

28401231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6685.

The product of its (nonzero) digits is 384, while the sum is 21.

The square root of 28401231 is about 5329.2805330551. The cubic root of 28401231 is about 305.1024684820.

The spelling of 28401231 in words is "twenty-eight million, four hundred one thousand, two hundred thirty-one".