21580100450 has 12 divisors (see below), whose sum is σ = 40138986930. Its totient is φ = 8632040160.

The previous prime is 21580100447. The next prime is 21580100527. The reversal of 21580100450 is 5400108512.

It can be written as a sum of positive squares in 3 ways, for example, as 21039212401 + 540888049 = 145049^2 + 23257^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 215800955 + ... + 215801054.

Almost surely, 2^21580100450 is an apocalyptic number.

21580100450 is a deficient number, since it is larger than the sum of its proper divisors (18558886480).

21580100450 is a wasteful number, since it uses less digits than its factorization.

21580100450 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 431602021 (or 431602016 counting only the distinct ones).

The product of its (nonzero) digits is 1600, while the sum is 26.

Adding to 21580100450 its reverse (5400108512), we get a palindrome (26980208962).

The spelling of 21580100450 in words is "twenty-one billion, five hundred eighty million, one hundred thousand, four hundred fifty".