21352777421 has 8 divisors (see below), whose sum is σ = 22298057664. Its totient is φ = 20408905440.

The previous prime is 21352777399. The next prime is 21352777451. The reversal of 21352777421 is 12477725312.

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 21352777421 - 2¹⁰ = 21352776397 is a prime.

It is a super-2 number, since 2×21352777421² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21352777451) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 321011 + ... + 381776.

It is an arithmetic number, because the mean of its divisors is an integer number (2787257208).

Almost surely, 2^21352777421 is an apocalyptic number.

It is an amenable number.

21352777421 is a deficient number, since it is larger than the sum of its proper divisors (945280243).

21352777421 is a wasteful number, since it uses less digits than its factorization.

21352777421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 704131.

The product of its digits is 164640, while the sum is 41.

The spelling of 21352777421 in words is "twenty-one billion, three hundred fifty-two million, seven hundred seventy-seven thousand, four hundred twenty-one".