21455746819 has 8 divisors (see below), whose sum is σ = 23127152832. Its totient is φ = 19787335680.

The previous prime is 21455746757. The next prime is 21455746847. The reversal of 21455746819 is 91864755412.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21455746819 - 2¹³ = 21455738627 is a prime.

It is a super-2 number, since 2×21455746819² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21455746619) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 733822 + ... + 762499.

It is an arithmetic number, because the mean of its divisors is an integer number (2890894104).

Almost surely, 2^21455746819 is an apocalyptic number.

21455746819 is a deficient number, since it is larger than the sum of its proper divisors (1671406013).

21455746819 is a wasteful number, since it uses less digits than its factorization.

21455746819 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1497437.

The product of its digits is 2419200, while the sum is 52.

The spelling of 21455746819 in words is "twenty-one billion, four hundred fifty-five million, seven hundred forty-six thousand, eight hundred nineteen".