20515227511 has 2 divisors, whose sum is σ = 20515227512. Its totient is φ = 20515227510.

The previous prime is 20515227493. The next prime is 20515227517. The reversal of 20515227511 is 11572251502.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20515227511 - 2⁹ = 20515226999 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20515227517) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10257613755 + 10257613756.

It is an arithmetic number, because the mean of its divisors is an integer number (10257613756).

Almost surely, 2^20515227511 is an apocalyptic number.

20515227511 is a deficient number, since it is larger than the sum of its proper divisors (1).

20515227511 is an equidigital number, since it uses as much as digits as its factorization.

20515227511 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7000, while the sum is 31.

The spelling of 20515227511 in words is "twenty billion, five hundred fifteen million, two hundred twenty-seven thousand, five hundred eleven".