2120731 has 2 divisors, whose sum is σ = 2120732. Its totient is φ = 2120730.

The previous prime is 2120693. The next prime is 2120747. The reversal of 2120731 is 1370212.

It is a happy number.

It is an a-pointer prime, because the next prime (2120747) can be obtained adding 2120731 to its sum of digits (16).

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2120731 is a prime.

It is a super-2 number, since 2×2120731² = 8994999948722, which contains 22 as substring.

2120731 is a lucky number.

It is not a weakly prime, because it can be changed into another prime (2120771) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1060365 + 1060366.

It is an arithmetic number, because the mean of its divisors is an integer number (1060366).

2^2120731 is an apocalyptic number.

2120731 is a deficient number, since it is larger than the sum of its proper divisors (1).

2120731 is an equidigital number, since it uses as much as digits as its factorization.

2120731 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 84, while the sum is 16.

The square root of 2120731 is about 1456.2729826513. The cubic root of 2120731 is about 128.4779292591.

Adding to 2120731 its reverse (1370212), we get a palindrome (3490943).

The spelling of 2120731 in words is "two million, one hundred twenty thousand, seven hundred thirty-one".