20951871436 has 48 divisors (see below), whose sum is σ = 38845255680. Its totient is φ = 9868288320.

The previous prime is 20951871431. The next prime is 20951871439. The reversal of 20951871436 is 63417815902.

It is a Harshad number since it is a multiple of its sum of digits (46).

It is not an unprimeable number, because it can be changed into a prime (20951871431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1668421 + ... + 1680931.

It is an arithmetic number, because the mean of its divisors is an integer number (809276160).

It is a 1-persistent number, because it is pandigital, but 2⋅20951871436 = 41903742872 is not.

Almost surely, 2^20951871436 is an apocalyptic number.

It is an amenable number.

20951871436 is a deficient number, since it is larger than the sum of its proper divisors (17893384244).

20951871436 is a wasteful number, since it uses less digits than its factorization.

20951871436 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12814 (or 12812 counting only the distinct ones).

The product of its (nonzero) digits is 362880, while the sum is 46.

The spelling of 20951871436 in words is "twenty billion, nine hundred fifty-one million, eight hundred seventy-one thousand, four hundred thirty-six".