21177896780428 has 48 divisors (see below), whose sum is σ = 37724222573856. Its totient is φ = 10401622318080.

The previous prime is 21177896780419. The next prime is 21177896780459. The reversal of 21177896780428 is 82408769877112.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23529175 + ... + 24412657.

It is an arithmetic number, because the mean of its divisors is an integer number (785921303622).

Almost surely, 2^{21177896780428} is an apocalyptic number.

It is an amenable number.

21177896780428 is a deficient number, since it is larger than the sum of its proper divisors (16546325793428).

21177896780428 is a wasteful number, since it uses less digits than its factorization.

21177896780428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 884074 (or 884072 counting only the distinct ones).

The product of its (nonzero) digits is 151732224, while the sum is 70.

The spelling of 21177896780428 in words is "twenty-one trillion, one hundred seventy-seven billion, eight hundred ninety-six million, seven hundred eighty thousand, four hundred twenty-eight".