21475342668 has 24 divisors (see below), whose sum is σ = 53963681968. Its totient is φ = 6607797696.

The previous prime is 21475342661. The next prime is 21475342703. The reversal of 21475342668 is 86624357412.

It is a super-2 number, since 2×21475342668² (a number of 21 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (48) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (21475342661) 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, 68831071 + ... + 68831382.

Almost surely, 2^21475342668 is an apocalyptic number.

It is an amenable number.

21475342668 is an abundant number, since it is smaller than the sum of its proper divisors (32488339300).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21475342668 is a wasteful number, since it uses less digits than its factorization.

21475342668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 137662473 (or 137662471 counting only the distinct ones).

The product of its digits is 1935360, while the sum is 48.

It can be divided in two parts, 2147 and 5342668, that added together give a triangular number (5344815 = T₃₂₆₉).

The spelling of 21475342668 in words is "twenty-one billion, four hundred seventy-five million, three hundred forty-two thousand, six hundred sixty-eight".