21254135634312 has 192 divisors, whose sum is σ = 61987608072000. Its totient is φ = 6055219183104.

The previous prime is 21254135634307. The next prime is 21254135634317. The reversal of 21254135634312 is 21343653145212.

It is an interprime number because it is at equal distance from previous prime (21254135634307) and next prime (21254135634317).

It is a Harshad number since it is a multiple of its sum of digits (42).

It is not an unprimeable number, because it can be changed into a prime (21254135634317) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2940117514 + ... + 2940124742.

It is an arithmetic number, because the mean of its divisors is an integer number (322852125375).

Almost surely, 2^{21254135634312} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21254135634312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30993804036000).

21254135634312 is an abundant number, since it is smaller than the sum of its proper divisors (40733472437688).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21254135634312 is a wasteful number, since it uses less digits than its factorization.

21254135634312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14068 (or 14057 counting only the distinct ones).

The product of its digits is 518400, while the sum is 42.

Adding to 21254135634312 its reverse (21343653145212), we get a palindrome (42597788779524).

The spelling of 21254135634312 in words is "twenty-one trillion, two hundred fifty-four billion, one hundred thirty-five million, six hundred thirty-four thousand, three hundred twelve".