7447681 has 2 divisors, whose sum is σ = 7447682. Its totient is φ = 7447680.

The previous prime is 7447669. The next prime is 7447697. The reversal of 7447681 is 1867447.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3837681 + 3610000 = 1959^2 + 1900^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-7447681 is a prime.

It is a super-2 number, since 2×7447681² = 110935904555522, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 7447681.

It is not a weakly prime, because it can be changed into another prime (7447631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3723840 + 3723841.

It is an arithmetic number, because the mean of its divisors is an integer number (3723841).

Almost surely, 2^7447681 is an apocalyptic number.

It is an amenable number.

7447681 is a deficient number, since it is larger than the sum of its proper divisors (1).

7447681 is an equidigital number, since it uses as much as digits as its factorization.

7447681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 37632, while the sum is 37.

The square root of 7447681 is about 2729.0439717967. The cubic root of 7447681 is about 195.2871596479.

It can be divided in two parts, 744768 and 1, that added together give a square (744769 = 863²).

The spelling of 7447681 in words is "seven million, four hundred forty-seven thousand, six hundred eighty-one".