21745167554 has 16 divisors (see below), whose sum is σ = 35588824416. Its totient is φ = 9882549600.

The previous prime is 21745167529. The next prime is 21745167571. The reversal of 21745167554 is 45576154712.

It is a junction number, because it is equal to n+sod(n) for n = 21745167499 and 21745167508.

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, 62249 + ... + 217635.

It is an arithmetic number, because the mean of its divisors is an integer number (2224301526).

Almost surely, 2^21745167554 is an apocalyptic number.

21745167554 is a deficient number, since it is larger than the sum of its proper divisors (13843656862).

21745167554 is a wasteful number, since it uses less digits than its factorization.

21745167554 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 161761.

The product of its digits is 1176000, while the sum is 47.

The spelling of 21745167554 in words is "twenty-one billion, seven hundred forty-five million, one hundred sixty-seven thousand, five hundred fifty-four".