7247389781 has 2 divisors, whose sum is σ = 7247389782. Its totient is φ = 7247389780.

The previous prime is 7247389757. The next prime is 7247389789. The reversal of 7247389781 is 1879837427.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6075423025 + 1171966756 = 77945^2 + 34234^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-7247389781 is a prime.

It is a super-2 number, since 2×7247389781² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7247389789) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3623694890 + 3623694891.

It is an arithmetic number, because the mean of its divisors is an integer number (3623694891).

Almost surely, 2^7247389781 is an apocalyptic number.

It is an amenable number.

7247389781 is a deficient number, since it is larger than the sum of its proper divisors (1).

7247389781 is an equidigital number, since it uses as much as digits as its factorization.

7247389781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4741632, while the sum is 56.

The square root of 7247389781 is about 85131.6027160302. The cubic root of 7247389781 is about 1935.2060203470.

The spelling of 7247389781 in words is "seven billion, two hundred forty-seven million, three hundred eighty-nine thousand, seven hundred eighty-one".