699648121 has 2 divisors, whose sum is σ = 699648122. Its totient is φ = 699648120.

The previous prime is 699648043. The next prime is 699648127. The reversal of 699648121 is 121846996.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 684554896 + 15093225 = 26164^2 + 3885^2 .

It is a cyclic number.

It is not a de Polignac number, because 699648121 - 2¹⁹ = 699123833 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (699648127) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 349824060 + 349824061.

It is an arithmetic number, because the mean of its divisors is an integer number (349824061).

Almost surely, 2^699648121 is an apocalyptic number.

It is an amenable number.

699648121 is a deficient number, since it is larger than the sum of its proper divisors (1).

699648121 is an equidigital number, since it uses as much as digits as its factorization.

699648121 is an evil number, because the sum of its binary digits is even.

The product of its digits is 186624, while the sum is 46.

The square root of 699648121 is about 26450.8623866973. The cubic root of 699648121 is about 887.7551983431.

The spelling of 699648121 in words is "six hundred ninety-nine million, six hundred forty-eight thousand, one hundred twenty-one".