21571761450 has 48 divisors (see below), whose sum is σ = 53518110336. Its totient is φ = 5750304000.

The previous prime is 21571761427. The next prime is 21571761457. The reversal of 21571761450 is 5416717512.

It is a super-2 number, since 2×21571761450² (a number of 21 digits) contains 22 as substring.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21571761399 and 21571761408.

It is not an unprimeable number, because it can be changed into a prime (21571761457) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 394479 + ... + 445821.

It is an arithmetic number, because the mean of its divisors is an integer number (1114960632).

Almost surely, 2^21571761450 is an apocalyptic number.

21571761450 is an abundant number, since it is smaller than the sum of its proper divisors (31946348886).

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

21571761450 is a wasteful number, since it uses less digits than its factorization.

21571761450 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54159 (or 54154 counting only the distinct ones).

The product of its (nonzero) digits is 58800, while the sum is 39.

The spelling of 21571761450 in words is "twenty-one billion, five hundred seventy-one million, seven hundred sixty-one thousand, four hundred fifty".