21555251043 has 8 divisors (see below), whose sum is σ = 30252984000. Its totient is φ = 13613842728.

The previous prime is 21555251017. The next prime is 21555251089. The reversal of 21555251043 is 34015255512.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21555251043 - 2¹⁰ = 21555250019 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21555250995 and 21555251013.

It is not an unprimeable number, because it can be changed into a prime (21555259043) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 189081093 + ... + 189081206.

It is an arithmetic number, because the mean of its divisors is an integer number (3781623000).

Almost surely, 2^21555251043 is an apocalyptic number.

21555251043 is a deficient number, since it is larger than the sum of its proper divisors (8697732957).

21555251043 is a wasteful number, since it uses less digits than its factorization.

21555251043 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 378162321.

The product of its (nonzero) digits is 30000, while the sum is 33.

The spelling of 21555251043 in words is "twenty-one billion, five hundred fifty-five million, two hundred fifty-one thousand, forty-three".