2905721 has 16 divisors (see below), whose sum is σ = 3677184. Its totient is φ = 2234304.

The previous prime is 2905703. The next prime is 2905739. The reversal of 2905721 is 1275092.

It is an interprime number because it is at equal distance from previous prime (2905703) and next prime (2905739).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2905721 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2905421) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2936 + ... + 3798.

It is an arithmetic number, because the mean of its divisors is an integer number (229824).

2^2905721 is an apocalyptic number.

It is an amenable number.

2905721 is a deficient number, since it is larger than the sum of its proper divisors (771463).

2905721 is a wasteful number, since it uses less digits than its factorization.

2905721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 920.

The product of its (nonzero) digits is 1260, while the sum is 26.

The square root of 2905721 is about 1704.6175524146. The cubic root of 2905721 is about 142.6980277472.

The spelling of 2905721 in words is "two million, nine hundred five thousand, seven hundred twenty-one".