28920901 has 4 divisors (see below), whose sum is σ = 28949932. Its totient is φ = 28891872.

The previous prime is 28920889. The next prime is 28920911. The reversal of 28920901 is 10902982.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 27552001 + 1368900 = 5249^2 + 1170^2 .

It is a cyclic number.

It is not a de Polignac number, because 28920901 - 2⁹ = 28920389 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 (28920911) 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, 12966 + ... + 15031.

It is an arithmetic number, because the mean of its divisors is an integer number (7237483).

Almost surely, 2^28920901 is an apocalyptic number.

It is an amenable number.

28920901 is a deficient number, since it is larger than the sum of its proper divisors (29031).

28920901 is a wasteful number, since it uses less digits than its factorization.

28920901 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29030.

The product of its (nonzero) digits is 2592, while the sum is 31.

The square root of 28920901 is about 5377.8156346234. The cubic root of 28920901 is about 306.9520981188.

The spelling of 28920901 in words is "twenty-eight million, nine hundred twenty thousand, nine hundred one".