21215415307 has 2 divisors, whose sum is σ = 21215415308. Its totient is φ = 21215415306.

The previous prime is 21215415301. The next prime is 21215415313. The reversal of 21215415307 is 70351451212.

It is a balanced prime because it is at equal distance from previous prime (21215415301) and next prime (21215415313).

It is a cyclic number.

It is not a de Polignac number, because 21215415307 - 2¹¹ = 21215413259 is a prime.

It is not a weakly prime, because it can be changed into another prime (21215415301) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10607707653 + 10607707654.

It is an arithmetic number, because the mean of its divisors is an integer number (10607707654).

Almost surely, 2^21215415307 is an apocalyptic number.

21215415307 is a deficient number, since it is larger than the sum of its proper divisors (1).

21215415307 is an equidigital number, since it uses as much as digits as its factorization.

21215415307 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8400, while the sum is 31.

Adding to 21215415307 its reverse (70351451212), we get a palindrome (91566866519).

The spelling of 21215415307 in words is "twenty-one billion, two hundred fifteen million, four hundred fifteen thousand, three hundred seven".