2723981 has 8 divisors (see below), whose sum is σ = 2947224. Its totient is φ = 2502720.

The previous prime is 2723969. The next prime is 2723989. The reversal of 2723981 is 1893272.

It can be written as a sum of positive squares in 4 ways, for example, as 17956 + 2706025 = 134^2 + 1645^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 2723981 - 2¹⁰ = 2722957 is a prime.

It is a super-2 number, since 2×2723981² = 14840144976722, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2723989) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3791 + ... + 4451.

It is an arithmetic number, because the mean of its divisors is an integer number (368403).

2^2723981 is an apocalyptic number.

It is an amenable number.

2723981 is a deficient number, since it is larger than the sum of its proper divisors (223243).

2723981 is a wasteful number, since it uses less digits than its factorization.

2723981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 991.

The product of its digits is 6048, while the sum is 32.

The square root of 2723981 is about 1650.4487268619. The cubic root of 2723981 is about 139.6587094981.

The spelling of 2723981 in words is "two million, seven hundred twenty-three thousand, nine hundred eighty-one".