28019977 has 2 divisors, whose sum is σ = 28019978. Its totient is φ = 28019976.

The previous prime is 28019969. The next prime is 28019993. The reversal of 28019977 is 77991082.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20286016 + 7733961 = 4504^2 + 2781^2 .

It is a cyclic number.

It is not a de Polignac number, because 28019977 - 2³ = 28019969 is a prime.

It is a super-2 number, since 2×28019977² = 1570238222161058, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (28019917) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14009988 + 14009989.

It is an arithmetic number, because the mean of its divisors is an integer number (14009989).

Almost surely, 2^28019977 is an apocalyptic number.

It is an amenable number.

28019977 is a deficient number, since it is larger than the sum of its proper divisors (1).

28019977 is an equidigital number, since it uses as much as digits as its factorization.

28019977 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 63504, while the sum is 43.

The square root of 28019977 is about 5293.3899346260. The cubic root of 28019977 is about 303.7310966124.

The spelling of 28019977 in words is "twenty-eight million, nineteen thousand, nine hundred seventy-seven".