28773031 has 4 divisors (see below), whose sum is σ = 32883472. Its totient is φ = 24662592.

The previous prime is 28773007. The next prime is 28773037. The reversal of 28773031 is 13037782.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13037782 = 2 ⋅6518891.

It is a cyclic number.

It is not a de Polignac number, because 28773031 - 2⁹ = 28772519 is a prime.

It is a super-2 number, since 2×28773031² = 1655774625853922, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28772984 and 28773002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28773037) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2055210 + ... + 2055223.

It is an arithmetic number, because the mean of its divisors is an integer number (8220868).

Almost surely, 2^28773031 is an apocalyptic number.

28773031 is a deficient number, since it is larger than the sum of its proper divisors (4110441).

28773031 is an equidigital number, since it uses as much as digits as its factorization.

28773031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4110440.

The product of its (nonzero) digits is 7056, while the sum is 31.

The square root of 28773031 is about 5364.0498692686. The cubic root of 28773031 is about 306.4280643772.

The spelling of 28773031 in words is "twenty-eight million, seven hundred seventy-three thousand, thirty-one".