28311901 has 2 divisors, whose sum is σ = 28311902. Its totient is φ = 28311900.

The previous prime is 28311887. The next prime is 28311947. The reversal of 28311901 is 10911382.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16402500 + 11909401 = 4050^2 + 3451^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28311901 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28311971) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14155950 + 14155951.

It is an arithmetic number, because the mean of its divisors is an integer number (14155951).

Almost surely, 2^28311901 is an apocalyptic number.

It is an amenable number.

28311901 is a deficient number, since it is larger than the sum of its proper divisors (1).

28311901 is an equidigital number, since it uses as much as digits as its factorization.

28311901 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 432, while the sum is 25.

The square root of 28311901 is about 5320.8928762004. The cubic root of 28311901 is about 304.7822543304.

The spelling of 28311901 in words is "twenty-eight million, three hundred eleven thousand, nine hundred one".