21106517054 has 12 divisors (see below), whose sum is σ = 36828718704. Its totient is φ = 9045650124.

The previous prime is 21106517041. The next prime is 21106517071. The reversal of 21106517054 is 45071560112.

It is a self number, because there is not a number n which added to its sum of digits gives 21106517054.

It is a congruent number.

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, 107686214 + ... + 107686409.

It is an arithmetic number, because the mean of its divisors is an integer number (3069059892).

Almost surely, 2^21106517054 is an apocalyptic number.

21106517054 is a deficient number, since it is larger than the sum of its proper divisors (15722201650).

21106517054 is a wasteful number, since it uses less digits than its factorization.

21106517054 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 215372639 (or 215372632 counting only the distinct ones).

The product of its (nonzero) digits is 8400, while the sum is 32.

The spelling of 21106517054 in words is "twenty-one billion, one hundred six million, five hundred seventeen thousand, fifty-four".