28222157 has 4 divisors (see below), whose sum is σ = 28984956. Its totient is φ = 27459360.

The previous prime is 28222153. The next prime is 28222169. The reversal of 28222157 is 75122282.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 22600516 + 5621641 = 4754^2 + 2371^2 .

It is a cyclic number.

It is not a de Polignac number, because 28222157 - 2² = 28222153 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28222153) 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, 381344 + ... + 381417.

It is an arithmetic number, because the mean of its divisors is an integer number (7246239).

Almost surely, 2^28222157 is an apocalyptic number.

It is an amenable number.

28222157 is a deficient number, since it is larger than the sum of its proper divisors (762799).

28222157 is an equidigital number, since it uses as much as digits as its factorization.

28222157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 762798.

The product of its digits is 4480, while the sum is 29.

The square root of 28222157 is about 5312.4530115569. The cubic root of 28222157 is about 304.4598771734.

The spelling of 28222157 in words is "twenty-eight million, two hundred twenty-two thousand, one hundred fifty-seven".