20439543778 has 32 divisors (see below), whose sum is σ = 33116106240. Its totient is φ = 9429747840.

The previous prime is 20439543769. The next prime is 20439543799. The reversal of 20439543778 is 87734593402.

It is an unprimeable number.

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, 934900 + ... + 956512.

It is an arithmetic number, because the mean of its divisors is an integer number (1034878320).

Almost surely, 2^20439543778 is an apocalyptic number.

20439543778 is a deficient number, since it is larger than the sum of its proper divisors (12676562462).

20439543778 is a wasteful number, since it uses less digits than its factorization.

20439543778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22282.

The product of its (nonzero) digits is 5080320, while the sum is 52.

The spelling of 20439543778 in words is "twenty billion, four hundred thirty-nine million, five hundred forty-three thousand, seven hundred seventy-eight".