28154381 has 2 divisors, whose sum is σ = 28154382. Its totient is φ = 28154380.

The previous prime is 28154377. The next prime is 28154393. The reversal of 28154381 is 18345182.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16362025 + 11792356 = 4045^2 + 3434^2 .

It is a cyclic number.

It is not a de Polignac number, because 28154381 - 2² = 28154377 is a prime.

It is a super-2 number, since 2×28154381² = 1585338338986322, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28154341) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14077190 + 14077191.

It is an arithmetic number, because the mean of its divisors is an integer number (14077191).

Almost surely, 2^28154381 is an apocalyptic number.

It is an amenable number.

28154381 is a deficient number, since it is larger than the sum of its proper divisors (1).

28154381 is an equidigital number, since it uses as much as digits as its factorization.

28154381 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7680, while the sum is 32.

The square root of 28154381 is about 5306.0702030787. The cubic root of 28154381 is about 304.2159599184.

The spelling of 28154381 in words is "twenty-eight million, one hundred fifty-four thousand, three hundred eighty-one".