21731217234 has 16 divisors (see below), whose sum is σ = 43516167840. Its totient is φ = 7234783520.

The previous prime is 21731217229. The next prime is 21731217253. The reversal of 21731217234 is 43271213712.

It is a super-2 number, since 2×21731217234² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21731217195 and 21731217204.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2233632 + ... + 2243339.

It is an arithmetic number, because the mean of its divisors is an integer number (2719760490).

Almost surely, 2^21731217234 is an apocalyptic number.

21731217234 is an abundant number, since it is smaller than the sum of its proper divisors (21784950606).

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

21731217234 is a wasteful number, since it uses less digits than its factorization.

21731217234 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4477785.

The product of its digits is 14112, while the sum is 33.

The spelling of 21731217234 in words is "twenty-one billion, seven hundred thirty-one million, two hundred seventeen thousand, two hundred thirty-four".