2905921 has 2 divisors, whose sum is σ = 2905922. Its totient is φ = 2905920.

The previous prime is 2905919. The next prime is 2905949. The reversal of 2905921 is 1295092.

It is an a-pointer prime, because the next prime (2905949) can be obtained adding 2905921 to its sum of digits (28).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2822400 + 83521 = 1680^2 + 289^2 .

It is a cyclic number.

It is not a de Polignac number, because 2905921 - 2¹ = 2905919 is a prime.

Together with 2905919, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2905921.

It is not a weakly prime, because it can be changed into another prime (2905901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1452960 + 1452961.

It is an arithmetic number, because the mean of its divisors is an integer number (1452961).

2^2905921 is an apocalyptic number.

It is an amenable number.

2905921 is a deficient number, since it is larger than the sum of its proper divisors (1).

2905921 is an equidigital number, since it uses as much as digits as its factorization.

2905921 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1620, while the sum is 28.

The square root of 2905921 is about 1704.6762155905. The cubic root of 2905921 is about 142.7013016278.

The spelling of 2905921 in words is "two million, nine hundred five thousand, nine hundred twenty-one".