21070155105 has 32 divisors (see below), whose sum is σ = 37635630720. Its totient is φ = 11184143040.

The previous prime is 21070154999. The next prime is 21070155133. The reversal of 21070155105 is 50155107012.

21070155105 is a `hidden beast` number, since 2 + 107 + 0 + 1 + 551 + 0 + 5 = 666.

It is not a de Polignac number, because 21070155105 - 2¹¹ = 21070153057 is a prime.

It is a super-2 number, since 2×21070155105² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 341362 + ... + 398331.

It is an arithmetic number, because the mean of its divisors is an integer number (1176113460).

Almost surely, 2^21070155105 is an apocalyptic number.

It is an amenable number.

21070155105 is a deficient number, since it is larger than the sum of its proper divisors (16565475615).

21070155105 is a wasteful number, since it uses less digits than its factorization.

21070155105 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 739918 (or 739912 counting only the distinct ones).

The product of its (nonzero) digits is 1750, while the sum is 27.

The spelling of 21070155105 in words is "twenty-one billion, seventy million, one hundred fifty-five thousand, one hundred five".