694812721 has 2 divisors, whose sum is σ = 694812722. Its totient is φ = 694812720.

The previous prime is 694812709. The next prime is 694812731. The reversal of 694812721 is 127218496.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 657358321 + 37454400 = 25639^2 + 6120^2 .

It is a cyclic number.

It is not a de Polignac number, because 694812721 - 2¹⁷ = 694681649 is a prime.

It is not a weakly prime, because it can be changed into another prime (694812731) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 347406360 + 347406361.

It is an arithmetic number, because the mean of its divisors is an integer number (347406361).

Almost surely, 2^694812721 is an apocalyptic number.

It is an amenable number.

694812721 is a deficient number, since it is larger than the sum of its proper divisors (1).

694812721 is an equidigital number, since it uses as much as digits as its factorization.

694812721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 48384, while the sum is 40.

The square root of 694812721 is about 26359.3004649213. The cubic root of 694812721 is about 885.7053208832.

The spelling of 694812721 in words is "six hundred ninety-four million, eight hundred twelve thousand, seven hundred twenty-one".