21121434510 has 96 divisors (see below), whose sum is σ = 56075102496. Its totient is φ = 5087596800.

The previous prime is 21121434479. The next prime is 21121434533. The reversal of 21121434510 is 1543412112.

It is a super-2 number, since 2×21121434510² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 551380 + ... + 588440.

It is an arithmetic number, because the mean of its divisors is an integer number (584115651).

Almost surely, 2^21121434510 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21121434510, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28037551248).

21121434510 is an abundant number, since it is smaller than the sum of its proper divisors (34953667986).

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

21121434510 is a wasteful number, since it uses less digits than its factorization.

21121434510 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37250 (or 37239 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 24.

Adding to 21121434510 its reverse (1543412112), we get a palindrome (22664846622).

It can be divided in two parts, 2112143 and 4510, that added together give a triangular number (2116653 = T₂₀₅₇).

The spelling of 21121434510 in words is "twenty-one billion, one hundred twenty-one million, four hundred thirty-four thousand, five hundred ten".