21374400120667 has 16 divisors (see below), whose sum is σ = 24360407635680. Its totient is φ = 18575474176000.

The previous prime is 21374400120653. The next prime is 21374400120679. The reversal of 21374400120667 is 76602100447312.

It is a cyclic number.

It is not a de Polignac number, because 21374400120667 - 2²⁷ = 21374265902939 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21374400120617) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 331672678 + ... + 331737115.

It is an arithmetic number, because the mean of its divisors is an integer number (1522525477230).

Almost surely, 2^{21374400120667} is an apocalyptic number.

21374400120667 is a deficient number, since it is larger than the sum of its proper divisors (2986007515013).

21374400120667 is a wasteful number, since it uses less digits than its factorization.

21374400120667 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 663409934.

The product of its (nonzero) digits is 338688, while the sum is 43.

Adding to 21374400120667 its reverse (76602100447312), we get a palindrome (97976500567979).

The spelling of 21374400120667 in words is "twenty-one trillion, three hundred seventy-four billion, four hundred million, one hundred twenty thousand, six hundred sixty-seven".