697272891221 has 2 divisors, whose sum is σ = 697272891222. Its totient is φ = 697272891220.

The previous prime is 697272891197. The next prime is 697272891269. The reversal of 697272891221 is 122198272796.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 676062172900 + 21210718321 = 822230^2 + 145639^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-697272891221 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (697272893221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 348636445610 + 348636445611.

It is an arithmetic number, because the mean of its divisors is an integer number (348636445611).

Almost surely, 2^697272891221 is an apocalyptic number.

It is an amenable number.

697272891221 is a deficient number, since it is larger than the sum of its proper divisors (1).

697272891221 is an equidigital number, since it uses as much as digits as its factorization.

697272891221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3048192, while the sum is 56.

The spelling of 697272891221 in words is "six hundred ninety-seven billion, two hundred seventy-two million, eight hundred ninety-one thousand, two hundred twenty-one".