28291979 has 8 divisors (see below), whose sum is σ = 29568000. Its totient is φ = 27044136.

The previous prime is 28291973. The next prime is 28291999. The reversal of 28291979 is 97919282.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28291979 is a prime.

It is a super-3 number, since 3×28291979³ (a number of 23 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (47).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28291973) 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, 4979 + ... + 9020.

It is an arithmetic number, because the mean of its divisors is an integer number (3696000).

Almost surely, 2^28291979 is an apocalyptic number.

28291979 is a deficient number, since it is larger than the sum of its proper divisors (1276021).

28291979 is a wasteful number, since it uses less digits than its factorization.

28291979 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14089.

The product of its digits is 163296, while the sum is 47.

The square root of 28291979 is about 5319.0204925343. The cubic root of 28291979 is about 304.7107496911.

The spelling of 28291979 in words is "twenty-eight million, two hundred ninety-one thousand, nine hundred seventy-nine".