21019681054 has 16 divisors (see below), whose sum is σ = 31854967200. Its totient is φ = 10401445600.

The previous prime is 21019681049. The next prime is 21019681069. The reversal of 21019681054 is 45018691012.

It is a super-2 number, since 2×21019681054² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 494487 + ... + 535309.

It is an arithmetic number, because the mean of its divisors is an integer number (1990935450).

Almost surely, 2^21019681054 is an apocalyptic number.

21019681054 is a deficient number, since it is larger than the sum of its proper divisors (10835286146).

21019681054 is a wasteful number, since it uses less digits than its factorization.

21019681054 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43475.

The product of its (nonzero) digits is 17280, while the sum is 37.

The spelling of 21019681054 in words is "twenty-one billion, nineteen million, six hundred eighty-one thousand, fifty-four".