28931722 has 8 divisors (see below), whose sum is σ = 45950436. Its totient is φ = 13614912.

The previous prime is 28931681. The next prime is 28931759. The reversal of 28931722 is 22713982.

It can be written as a sum of positive squares in 2 ways, for example, as 27657081 + 1274641 = 5259^2 + 1129^2 .

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

It is a Harshad number since it is a multiple of its sum of digits (34), and also a Moran number because the ratio is a prime number: 850933 = 28931722 / (2 + 8 + 9 + 3 + 1 + 7 + 2 + 2).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 425433 + ... + 425500.

Almost surely, 2^28931722 is an apocalyptic number.

28931722 is a deficient number, since it is larger than the sum of its proper divisors (17018714).

28931722 is a wasteful number, since it uses less digits than its factorization.

28931722 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 850952.

The product of its digits is 12096, while the sum is 34.

The square root of 28931722 is about 5378.8216181614. The cubic root of 28931722 is about 306.9903762540.

It can be divided in two parts, 2893 and 1722, that multiplied together give a triangular number (4981746 = T₃₁₅₆).

The spelling of 28931722 in words is "twenty-eight million, nine hundred thirty-one thousand, seven hundred twenty-two".