28401387 has 8 divisors (see below), whose sum is σ = 43278336. Its totient is φ = 16229352.

The previous prime is 28401379. The next prime is 28401419. The reversal of 28401387 is 78310482.

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

It is not a de Polignac number, because 28401387 - 2³ = 28401379 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28401287) 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, 676203 + ... + 676244.

It is an arithmetic number, because the mean of its divisors is an integer number (5409792).

Almost surely, 2^28401387 is an apocalyptic number.

28401387 is a deficient number, since it is larger than the sum of its proper divisors (14876949).

28401387 is a wasteful number, since it uses less digits than its factorization.

28401387 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1352457.

The product of its (nonzero) digits is 10752, while the sum is 33.

The square root of 28401387 is about 5329.2951691570. The cubic root of 28401387 is about 305.1030270951.

The spelling of 28401387 in words is "twenty-eight million, four hundred one thousand, three hundred eighty-seven".