20854393977 has 16 divisors (see below), whose sum is σ = 29276744000. Its totient is φ = 13167857664.

The previous prime is 20854393961. The next prime is 20854393981. The reversal of 20854393977 is 77939345802.

It is not a de Polignac number, because 20854393977 - 2⁴ = 20854393961 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (57).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20854393907) 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, 191049 + ... + 279657.

It is an arithmetic number, because the mean of its divisors is an integer number (1829796500).

Almost surely, 2^20854393977 is an apocalyptic number.

It is an amenable number.

20854393977 is a deficient number, since it is larger than the sum of its proper divisors (8422350023).

20854393977 is a wasteful number, since it uses less digits than its factorization.

20854393977 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92760.

The product of its (nonzero) digits is 11430720, while the sum is 57.

The spelling of 20854393977 in words is "twenty billion, eight hundred fifty-four million, three hundred ninety-three thousand, nine hundred seventy-seven".