21157726145 has 32 divisors (see below), whose sum is σ = 26613970944. Its totient is φ = 16127424000.

The previous prime is 21157726103. The next prime is 21157726171. The reversal of 21157726145 is 54162775112.

It is not a de Polignac number, because 21157726145 - 2¹⁶ = 21157660609 is a prime.

It is a super-2 number, since 2×21157726145² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

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, 8292620 + ... + 8295170.

It is an arithmetic number, because the mean of its divisors is an integer number (831686592).

Almost surely, 2^21157726145 is an apocalyptic number.

It is an amenable number.

21157726145 is a deficient number, since it is larger than the sum of its proper divisors (5456244799).

21157726145 is a wasteful number, since it uses less digits than its factorization.

21157726145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3393.

The product of its digits is 117600, while the sum is 41.

The spelling of 21157726145 in words is "twenty-one billion, one hundred fifty-seven million, seven hundred twenty-six thousand, one hundred forty-five".