690021012221 has 2 divisors, whose sum is σ = 690021012222. Its totient is φ = 690021012220.

The previous prime is 690021012217. The next prime is 690021012223. The reversal of 690021012221 is 122210120096.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 474878104996 + 215142907225 = 689114^2 + 463835^2 .

It is a cyclic number.

It is not a de Polignac number, because 690021012221 - 2² = 690021012217 is a prime.

It is a super-2 number, since 2×690021012221² (a number of 24 digits) contains 22 as substring.

Together with 690021012223, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (690021012223) 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, 345010506110 + 345010506111.

It is an arithmetic number, because the mean of its divisors is an integer number (345010506111).

Almost surely, 2^690021012221 is an apocalyptic number.

It is an amenable number.

690021012221 is a deficient number, since it is larger than the sum of its proper divisors (1).

690021012221 is an equidigital number, since it uses as much as digits as its factorization.

690021012221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 864, while the sum is 26.

The spelling of 690021012221 in words is "six hundred ninety billion, twenty-one million, twelve thousand, two hundred twenty-one".