2501721 has 12 divisors (see below), whose sum is σ = 3632148. Its totient is φ = 1659264.

The previous prime is 2501699. The next prime is 2501761. The reversal of 2501721 is 1271052.

It can be written as a sum of positive squares in 2 ways, for example, as 876096 + 1625625 = 936^2 + 1275^2 .

It is not a de Polignac number, because 2501721 - 2⁵ = 2501689 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2501694 and 2501703.

It is not an unprimeable number, because it can be changed into a prime (2501761) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1501 + ... + 2693.

It is an arithmetic number, because the mean of its divisors is an integer number (302679).

2^2501721 is an apocalyptic number.

It is an amenable number.

2501721 is a deficient number, since it is larger than the sum of its proper divisors (1130427).

2501721 is a wasteful number, since it uses less digits than its factorization.

2501721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1432 (or 1429 counting only the distinct ones).

The product of its (nonzero) digits is 140, while the sum is 18.

The square root of 2501721 is about 1581.6829644401. The cubic root of 2501721 is about 135.7520171042.

Adding to 2501721 its reverse (1271052), we get a palindrome (3772773).

The spelling of 2501721 in words is "two million, five hundred one thousand, seven hundred twenty-one".