21085157311 has 2 divisors, whose sum is σ = 21085157312. Its totient is φ = 21085157310.

The previous prime is 21085157297. The next prime is 21085157407. The reversal of 21085157311 is 11375158012.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21085157311 - 2²³ = 21076768703 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21085107311) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10542578655 + 10542578656.

It is an arithmetic number, because the mean of its divisors is an integer number (10542578656).

Almost surely, 2^21085157311 is an apocalyptic number.

21085157311 is a deficient number, since it is larger than the sum of its proper divisors (1).

21085157311 is an equidigital number, since it uses as much as digits as its factorization.

21085157311 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8400, while the sum is 34.

The spelling of 21085157311 in words is "twenty-one billion, eighty-five million, one hundred fifty-seven thousand, three hundred eleven".