721112257 has 2 divisors, whose sum is σ = 721112258. Its totient is φ = 721112256.

The previous prime is 721112243. The next prime is 721112303. The reversal of 721112257 is 752211127.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 688747536 + 32364721 = 26244^2 + 5689^2 .

It is an emirp because it is prime and its reverse (752211127) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-721112257 is a prime.

It is not a weakly prime, because it can be changed into another prime (721112657) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 360556128 + 360556129.

It is an arithmetic number, because the mean of its divisors is an integer number (360556129).

Almost surely, 2^721112257 is an apocalyptic number.

It is an amenable number.

721112257 is a deficient number, since it is larger than the sum of its proper divisors (1).

721112257 is an equidigital number, since it uses as much as digits as its factorization.

721112257 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1960, while the sum is 28.

The square root of 721112257 is about 26853.5334174108. The cubic root of 721112257 is about 896.7422372120.

The spelling of 721112257 in words is "seven hundred twenty-one million, one hundred twelve thousand, two hundred fifty-seven".