7213899521 has 2 divisors, whose sum is σ = 7213899522. Its totient is φ = 7213899520.

The previous prime is 7213899421. The next prime is 7213899523. The reversal of 7213899521 is 1259983127.

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., 4084615921 + 3129283600 = 63911^2 + 55940^2 .

It is a cyclic number.

It is not a de Polignac number, because 7213899521 - 2²⁶ = 7146790657 is a prime.

Together with 7213899523, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (7213899523) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3606949760 + 3606949761.

It is an arithmetic number, because the mean of its divisors is an integer number (3606949761).

Almost surely, 2^7213899521 is an apocalyptic number.

It is an amenable number.

7213899521 is a deficient number, since it is larger than the sum of its proper divisors (1).

7213899521 is an equidigital number, since it uses as much as digits as its factorization.

7213899521 is an evil number, because the sum of its binary digits is even.

The product of its digits is 272160, while the sum is 47.

The square root of 7213899521 is about 84934.6779648925. The cubic root of 7213899521 is about 1932.2205482491.

The spelling of 7213899521 in words is "seven billion, two hundred thirteen million, eight hundred ninety-nine thousand, five hundred twenty-one".