21619601782723 has 4 divisors (see below), whose sum is σ = 24708116323120. Its totient is φ = 18531087242328.

The previous prime is 21619601782657. The next prime is 21619601782759. The reversal of 21619601782723 is 32728710691612.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21619601782723 - 2¹⁷ = 21619601651651 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21619601582723) 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, 1544257270188 + ... + 1544257270201.

It is an arithmetic number, because the mean of its divisors is an integer number (6177029080780).

Almost surely, 2^{21619601782723} is an apocalyptic number.

21619601782723 is a deficient number, since it is larger than the sum of its proper divisors (3088514540397).

21619601782723 is an equidigital number, since it uses as much as digits as its factorization.

21619601782723 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3088514540396.

The product of its (nonzero) digits is 3048192, while the sum is 55.

The spelling of 21619601782723 in words is "twenty-one trillion, six hundred nineteen billion, six hundred one million, seven hundred eighty-two thousand, seven hundred twenty-three".