21667155671667 has 32 divisors (see below), whose sum is σ = 32802632974080. Its totient is φ = 12601011265920.

The previous prime is 21667155671663. The next prime is 21667155671671. The reversal of 21667155671667 is 76617655176612.

It is an interprime number because it is at equal distance from previous prime (21667155671663) and next prime (21667155671671).

It is not a de Polignac number, because 21667155671667 - 2² = 21667155671663 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21667155671598 and 21667155671607.

It is not an unprimeable number, because it can be changed into a prime (21667155671663) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 69294028 + ... + 69606009.

It is an arithmetic number, because the mean of its divisors is an integer number (1025082280440).

Almost surely, 2^{21667155671667} is an apocalyptic number.

21667155671667 is a deficient number, since it is larger than the sum of its proper divisors (11135477302413).

21667155671667 is a wasteful number, since it uses less digits than its factorization.

21667155671667 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 138900243.

The product of its digits is 133358400, while the sum is 66.

The spelling of 21667155671667 in words is "twenty-one trillion, six hundred sixty-seven billion, one hundred fifty-five million, six hundred seventy-one thousand, six hundred sixty-seven".