20787757478011 has 2 divisors, whose sum is σ = 20787757478012. Its totient is φ = 20787757478010.

The previous prime is 20787757478009. The next prime is 20787757478023. The reversal of 20787757478011 is 11087475778702.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20787757478011 - 2¹ = 20787757478009 is a prime.

It is a super-2 number, since 2×20787757478011² (a number of 27 digits) contains 22 as substring.

Together with 20787757478009, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (20787757478041) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10393878739005 + 10393878739006.

It is an arithmetic number, because the mean of its divisors is an integer number (10393878739006).

Almost surely, 2^{20787757478011} is an apocalyptic number.

20787757478011 is a deficient number, since it is larger than the sum of its proper divisors (1).

20787757478011 is an equidigital number, since it uses as much as digits as its factorization.

20787757478011 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 43025920, while the sum is 64.

The spelling of 20787757478011 in words is "twenty trillion, seven hundred eighty-seven billion, seven hundred fifty-seven million, four hundred seventy-eight thousand, eleven".