694648621 has 2 divisors, whose sum is σ = 694648622. Its totient is φ = 694648620.

The previous prime is 694648613. The next prime is 694648627. The reversal of 694648621 is 126846496.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 406022500 + 288626121 = 20150^2 + 16989^2 .

It is a cyclic number.

It is not a de Polignac number, because 694648621 - 2³ = 694648613 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (694648627) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 347324310 + 347324311.

It is an arithmetic number, because the mean of its divisors is an integer number (347324311).

Almost surely, 2^694648621 is an apocalyptic number.

It is an amenable number.

694648621 is a deficient number, since it is larger than the sum of its proper divisors (1).

694648621 is an equidigital number, since it uses as much as digits as its factorization.

694648621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 497664, while the sum is 46.

The square root of 694648621 is about 26356.1875277894. The cubic root of 694648621 is about 885.6355871345.

The spelling of 694648621 in words is "six hundred ninety-four million, six hundred forty-eight thousand, six hundred twenty-one".