21478551758 has 16 divisors (see below), whose sum is σ = 32646792960. Its totient is φ = 10596463800.

The previous prime is 21478551751. The next prime is 21478551833. The reversal of 21478551758 is 85715587412.

It is a super-2 number, since 2×21478551758² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21478551751) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 204953 + ... + 291483.

It is an arithmetic number, because the mean of its divisors is an integer number (2040424560).

Almost surely, 2^21478551758 is an apocalyptic number.

21478551758 is a deficient number, since it is larger than the sum of its proper divisors (11168241202).

21478551758 is a wasteful number, since it uses less digits than its factorization.

21478551758 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 88183.

The product of its digits is 3136000, while the sum is 53.

The spelling of 21478551758 in words is "twenty-one billion, four hundred seventy-eight million, five hundred fifty-one thousand, seven hundred fifty-eight".