28687901 has 4 divisors (see below), whose sum is σ = 31295904. Its totient is φ = 26079900.

The previous prime is 28687889. The next prime is 28687909. The reversal of 28687901 is 10978682.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a de Polignac number, because none of the positive numbers 2^k-28687901 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 (28687909) 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, 1303985 + ... + 1304006.

It is an arithmetic number, because the mean of its divisors is an integer number (7823976).

Almost surely, 2^28687901 is an apocalyptic number.

It is an amenable number.

28687901 is a deficient number, since it is larger than the sum of its proper divisors (2608003).

28687901 is a wasteful number, since it uses less digits than its factorization.

28687901 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2608002.

The product of its (nonzero) digits is 48384, while the sum is 41.

The square root of 28687901 is about 5356.1087554306. The cubic root of 28687901 is about 306.1255589933.

The spelling of 28687901 in words is "twenty-eight million, six hundred eighty-seven thousand, nine hundred one".