21927277878393 has 4 divisors (see below), whose sum is σ = 29236370504528. Its totient is φ = 14618185252260.

The previous prime is 21927277878343. The next prime is 21927277878433. The reversal of 21927277878393 is 39387877272912.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 21927277878393 - 2¹⁸ = 21927277616249 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21927277878343) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3654546313063 + ... + 3654546313068.

It is an arithmetic number, because the mean of its divisors is an integer number (7309092626132).

Almost surely, 2^{21927277878393} is an apocalyptic number.

It is an amenable number.

21927277878393 is a deficient number, since it is larger than the sum of its proper divisors (7309092626135).

21927277878393 is an equidigital number, since it uses as much as digits as its factorization.

21927277878393 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7309092626134.

The product of its digits is 896168448, while the sum is 75.

The spelling of 21927277878393 in words is "twenty-one trillion, nine hundred twenty-seven billion, two hundred seventy-seven million, eight hundred seventy-eight thousand, three hundred ninety-three".