28725101 has 2 divisors, whose sum is σ = 28725102. Its totient is φ = 28725100.

The previous prime is 28725089. The next prime is 28725139. The reversal of 28725101 is 10152782.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 26275876 + 2449225 = 5126^2 + 1565^2 .

It is a cyclic number.

It is not a de Polignac number, because 28725101 - 2¹⁴ = 28708717 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28725181) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14362550 + 14362551.

It is an arithmetic number, because the mean of its divisors is an integer number (14362551).

Almost surely, 2^28725101 is an apocalyptic number.

It is an amenable number.

28725101 is a deficient number, since it is larger than the sum of its proper divisors (1).

28725101 is an equidigital number, since it uses as much as digits as its factorization.

28725101 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1120, while the sum is 26.

The square root of 28725101 is about 5359.5803007325. The cubic root of 28725101 is about 306.2578209304.

Adding to 28725101 its reverse (10152782), we get a palindrome (38877883).

The spelling of 28725101 in words is "twenty-eight million, seven hundred twenty-five thousand, one hundred one".