20946649819 has 2 divisors, whose sum is σ = 20946649820. Its totient is φ = 20946649818.

The previous prime is 20946649799. The next prime is 20946649831. The reversal of 20946649819 is 91894664902.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20946649819 - 2⁹ = 20946649307 is a prime.

It is a super-2 number, since 2×20946649819² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20946649519) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10473324909 + 10473324910.

It is an arithmetic number, because the mean of its divisors is an integer number (10473324910).

Almost surely, 2^20946649819 is an apocalyptic number.

20946649819 is a deficient number, since it is larger than the sum of its proper divisors (1).

20946649819 is an equidigital number, since it uses as much as digits as its factorization.

20946649819 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6718464, while the sum is 58.

The spelling of 20946649819 in words is "twenty billion, nine hundred forty-six million, six hundred forty-nine thousand, eight hundred nineteen".