28612901 has 4 divisors (see below), whose sum is σ = 28625100. Its totient is φ = 28600704.

The previous prime is 28612849. The next prime is 28612967. The reversal of 28612901 is 10921682.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 10921682 = 2 ⋅5460841.

It can be written as a sum of positive squares in 2 ways, for example, as 27050401 + 1562500 = 5201^2 + 1250^2 .

It is a cyclic number.

It is not a de Polignac number, because 28612901 - 2¹⁴ = 28596517 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 (28618901) 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, 1346 + ... + 7683.

It is an arithmetic number, because the mean of its divisors is an integer number (7156275).

Almost surely, 2^28612901 is an apocalyptic number.

It is an amenable number.

28612901 is a deficient number, since it is larger than the sum of its proper divisors (12199).

28612901 is an equidigital number, since it uses as much as digits as its factorization.

28612901 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12198.

The product of its (nonzero) digits is 1728, while the sum is 29.

The square root of 28612901 is about 5349.1028219693. The cubic root of 28612901 is about 305.8585538197.

It can be divided in two parts, 286 and 12901, that multiplied together give a triangular number (3689686 = T₂₇₁₆).

The spelling of 28612901 in words is "twenty-eight million, six hundred twelve thousand, nine hundred one".