20638062991 has 48 divisors (see below), whose sum is σ = 26169701376. Its totient is φ = 16131032064.

The previous prime is 20638062989. The next prime is 20638063049. The reversal of 20638062991 is 19926083602.

It is not a de Polignac number, because 20638062991 - 2¹ = 20638062989 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20638062901) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 27262585 + ... + 27263341.

It is an arithmetic number, because the mean of its divisors is an integer number (545202112).

Almost surely, 2^20638062991 is an apocalyptic number.

20638062991 is a deficient number, since it is larger than the sum of its proper divisors (5531638385).

20638062991 is a wasteful number, since it uses less digits than its factorization.

20638062991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1248 (or 1241 counting only the distinct ones).

The product of its (nonzero) digits is 279936, while the sum is 46.

The spelling of 20638062991 in words is "twenty billion, six hundred thirty-eight million, sixty-two thousand, nine hundred ninety-one".