28791947 has 2 divisors, whose sum is σ = 28791948. Its totient is φ = 28791946.

The previous prime is 28791943. The next prime is 28791949. The reversal of 28791947 is 74919782.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 28791947 - 2² = 28791943 is a prime.

Together with 28791949, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (28791943) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14395973 + 14395974.

It is an arithmetic number, because the mean of its divisors is an integer number (14395974).

Almost surely, 2^28791947 is an apocalyptic number.

28791947 is a deficient number, since it is larger than the sum of its proper divisors (1).

28791947 is an equidigital number, since it uses as much as digits as its factorization.

28791947 is an evil number, because the sum of its binary digits is even.

The product of its digits is 254016, while the sum is 47.

The square root of 28791947 is about 5365.8127995673. The cubic root of 28791947 is about 306.4952004337.

The spelling of 28791947 in words is "twenty-eight million, seven hundred ninety-one thousand, nine hundred forty-seven".