7215827621 has 2 divisors, whose sum is σ = 7215827622. Its totient is φ = 7215827620.

The previous prime is 7215827611. The next prime is 7215827629. The reversal of 7215827621 is 1267285127.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4330956100 + 2884871521 = 65810^2 + 53711^2 .

It is an emirp because it is prime and its reverse (1267285127) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 7215827621 - 2⁶ = 7215827557 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7215827629) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3607913810 + 3607913811.

It is an arithmetic number, because the mean of its divisors is an integer number (3607913811).

Almost surely, 2^7215827621 is an apocalyptic number.

It is an amenable number.

7215827621 is a deficient number, since it is larger than the sum of its proper divisors (1).

7215827621 is an equidigital number, since it uses as much as digits as its factorization.

7215827621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 94080, while the sum is 41.

The square root of 7215827621 is about 84946.0276940600. The cubic root of 7215827621 is about 1932.3926781105.

The spelling of 7215827621 in words is "seven billion, two hundred fifteen million, eight hundred twenty-seven thousand, six hundred twenty-one".