28379947 has 2 divisors, whose sum is σ = 28379948. Its totient is φ = 28379946.

The previous prime is 28379929. The next prime is 28379959. The reversal of 28379947 is 74997382.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 28379947 - 2²³ = 19991339 is a prime.

It is a super-3 number, since 3×28379947³ (a number of 23 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 28379947.

It is not a weakly prime, because it can be changed into another prime (28379047) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14189973 + 14189974.

It is an arithmetic number, because the mean of its divisors is an integer number (14189974).

Almost surely, 2^28379947 is an apocalyptic number.

28379947 is a deficient number, since it is larger than the sum of its proper divisors (1).

28379947 is an equidigital number, since it uses as much as digits as its factorization.

28379947 is an evil number, because the sum of its binary digits is even.

The product of its digits is 762048, while the sum is 49.

The square root of 28379947 is about 5327.2832663563. The cubic root of 28379947 is about 305.0262344181.

The spelling of 28379947 in words is "twenty-eight million, three hundred seventy-nine thousand, nine hundred forty-seven".