720246731 has 2 divisors, whose sum is σ = 720246732. Its totient is φ = 720246730.

The previous prime is 720246721. The next prime is 720246739. The reversal of 720246731 is 137642027.

It is a strong prime.

It is an emirp because it is prime and its reverse (137642027) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-720246731 is a prime.

It is a super-2 number, since 2×720246731² = 1037510707032372722, which contains 22 as substring.

It is a Sophie Germain prime.

It is equal to p_37246136 and since 720246731 and 37246136 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (720246739) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 360123365 + 360123366.

It is an arithmetic number, because the mean of its divisors is an integer number (360123366).

Almost surely, 2^720246731 is an apocalyptic number.

720246731 is a deficient number, since it is larger than the sum of its proper divisors (1).

720246731 is an equidigital number, since it uses as much as digits as its factorization.

720246731 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 14112, while the sum is 32.

The square root of 720246731 is about 26837.4128969243. The cubic root of 720246731 is about 896.3833173853.

Adding to 720246731 its reverse (137642027), we get a palindrome (857888758).

The spelling of 720246731 in words is "seven hundred twenty million, two hundred forty-six thousand, seven hundred thirty-one".