721130947 has 2 divisors, whose sum is σ = 721130948. Its totient is φ = 721130946.

The previous prime is 721130909. The next prime is 721130953. The reversal of 721130947 is 749031127.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 721130947 - 2¹⁵ = 721098179 is a prime.

It is a super-2 number, since 2×721130947² = 1040059685442233618, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (721130957) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 360565473 + 360565474.

It is an arithmetic number, because the mean of its divisors is an integer number (360565474).

Almost surely, 2^721130947 is an apocalyptic number.

721130947 is a deficient number, since it is larger than the sum of its proper divisors (1).

721130947 is an equidigital number, since it uses as much as digits as its factorization.

721130947 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10584, while the sum is 34.

The square root of 721130947 is about 26853.8814140526. The cubic root of 721130947 is about 896.7499844882.

The spelling of 721130947 in words is "seven hundred twenty-one million, one hundred thirty thousand, nine hundred forty-seven".