28401947 has 8 divisors (see below), whose sum is σ = 32824800. Its totient is φ = 24070464.

The previous prime is 28401937. The next prime is 28402007. The reversal of 28401947 is 74910482.

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 28401947 - 2⁴ = 28401931 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28401937) 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, 22172 + ... + 23417.

It is an arithmetic number, because the mean of its divisors is an integer number (4103100).

Almost surely, 2^28401947 is an apocalyptic number.

28401947 is a deficient number, since it is larger than the sum of its proper divisors (4422853).

28401947 is an equidigital number, since it uses as much as digits as its factorization.

28401947 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45685.

The product of its (nonzero) digits is 16128, while the sum is 35.

The square root of 28401947 is about 5329.3477086788. The cubic root of 28401947 is about 305.1050323560.

The spelling of 28401947 in words is "twenty-eight million, four hundred one thousand, nine hundred forty-seven".