21343634040 has 384 divisors, whose sum is σ = 70718598720. Its totient is φ = 5148057600.

The previous prime is 21343634017. The next prime is 21343634051. The reversal of 21343634040 is 4043634312.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 21343633989 and 21343634007.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 108343222 + ... + 108343418.

Almost surely, 2^21343634040 is an apocalyptic number.

21343634040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21343634040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35359299360).

21343634040 is an abundant number, since it is smaller than the sum of its proper divisors (49374964680).

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

21343634040 is a wasteful number, since it uses less digits than its factorization.

21343634040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 351 (or 328 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 30.

The spelling of 21343634040 in words is "twenty-one billion, three hundred forty-three million, six hundred thirty-four thousand, forty".