28537661 has 2 divisors, whose sum is σ = 28537662. Its totient is φ = 28537660.

The previous prime is 28537657. The next prime is 28537667. The reversal of 28537661 is 16673582.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 28026436 + 511225 = 5294^2 + 715^2 .

It is a cyclic number.

It is not a de Polignac number, because 28537661 - 2² = 28537657 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28537667) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14268830 + 14268831.

It is an arithmetic number, because the mean of its divisors is an integer number (14268831).

Almost surely, 2^28537661 is an apocalyptic number.

It is an amenable number.

28537661 is a deficient number, since it is larger than the sum of its proper divisors (1).

28537661 is an equidigital number, since it uses as much as digits as its factorization.

28537661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 60480, while the sum is 38.

The square root of 28537661 is about 5342.0652373403. The cubic root of 28537661 is about 305.5902249930.

The spelling of 28537661 in words is "twenty-eight million, five hundred thirty-seven thousand, six hundred sixty-one".