21126313546 has 8 divisors (see below), whose sum is σ = 34127121924. Its totient is φ = 9750606240.

The previous prime is 21126313543. The next prime is 21126313561. The reversal of 21126313546 is 64531362112.

It can be written as a sum of positive squares in 2 ways, for example, as 19741655025 + 1384658521 = 140505^2 + 37211^2 .

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

It is a super-2 number, since 2×21126313546² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21126313543) 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, 406275235 + ... + 406275286.

Almost surely, 2^21126313546 is an apocalyptic number.

21126313546 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

21126313546 is a deficient number, since it is larger than the sum of its proper divisors (13000808378).

21126313546 is a wasteful number, since it uses less digits than its factorization.

21126313546 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 812550536.

The product of its digits is 25920, while the sum is 34.

Adding to 21126313546 its reverse (64531362112), we get a palindrome (85657675658).

The spelling of 21126313546 in words is "twenty-one billion, one hundred twenty-six million, three hundred thirteen thousand, five hundred forty-six".