21267537471 has 20 divisors (see below), whose sum is σ = 31931318232. Its totient is φ = 14106376368.

The previous prime is 21267537461. The next prime is 21267537479. The reversal of 21267537471 is 17473576212.

21267537471 is a `hidden beast` number, since 2 + 12 + 67 + 537 + 47 + 1 = 666.

It is not a de Polignac number, because 21267537471 - 2⁶ = 21267537407 is a prime.

It is a super-3 number, since 3×21267537471³ (a number of 32 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21267537479) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 650445 + ... + 682358.

Almost surely, 2^21267537471 is an apocalyptic number.

21267537471 is a deficient number, since it is larger than the sum of its proper divisors (10663780761).

21267537471 is a wasteful number, since it uses less digits than its factorization.

21267537471 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1333012 (or 1333003 counting only the distinct ones).

The product of its digits is 493920, while the sum is 45.

The spelling of 21267537471 in words is "twenty-one billion, two hundred sixty-seven million, five hundred thirty-seven thousand, four hundred seventy-one".