21380507527 has 2 divisors, whose sum is σ = 21380507528. Its totient is φ = 21380507526.

The previous prime is 21380507501. The next prime is 21380507633. The reversal of 21380507527 is 72570508312.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21380507527 - 2¹¹ = 21380505479 is a prime.

It is a super-2 number, since 2×21380507527² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21380507527.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21380307527) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10690253763 + 10690253764.

It is an arithmetic number, because the mean of its divisors is an integer number (10690253764).

Almost surely, 2^21380507527 is an apocalyptic number.

21380507527 is a deficient number, since it is larger than the sum of its proper divisors (1).

21380507527 is an equidigital number, since it uses as much as digits as its factorization.

21380507527 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 117600, while the sum is 40.

The spelling of 21380507527 in words is "twenty-one billion, three hundred eighty million, five hundred seven thousand, five hundred twenty-seven".