28401081 has 16 divisors (see below), whose sum is σ = 38486400. Its totient is φ = 18627840.

The previous prime is 28401049. The next prime is 28401083. The reversal of 28401081 is 18010482.

It is not a de Polignac number, because 28401081 - 2⁵ = 28401049 is a prime.

It is a super-2 number, since 2×28401081² = 1613242803937122, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (28401083) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 67251 + ... + 67671.

It is an arithmetic number, because the mean of its divisors is an integer number (2405400).

Almost surely, 2^28401081 is an apocalyptic number.

It is an amenable number.

28401081 is a deficient number, since it is larger than the sum of its proper divisors (10085319).

28401081 is a wasteful number, since it uses less digits than its factorization.

28401081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 736.

The product of its (nonzero) digits is 512, while the sum is 24.

The square root of 28401081 is about 5329.2664598423. The cubic root of 28401081 is about 305.1019313521.

The spelling of 28401081 in words is "twenty-eight million, four hundred one thousand, eighty-one".