21404501872969 has 2 divisors, whose sum is σ = 21404501872970. Its totient is φ = 21404501872968.

The previous prime is 21404501872951. The next prime is 21404501872997. The reversal of 21404501872969 is 96927810540412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21147011593744 + 257490279225 = 4598588^2 + 507435^2 .

It is a cyclic number.

It is not a de Polignac number, because 21404501872969 - 2⁷ = 21404501872841 is a prime.

It is a super-2 number, since 2×21404501872969² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21404501852969) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10702250936484 + 10702250936485.

It is an arithmetic number, because the mean of its divisors is an integer number (10702250936485).

Almost surely, 2^{21404501872969} is an apocalyptic number.

It is an amenable number.

21404501872969 is a deficient number, since it is larger than the sum of its proper divisors (1).

21404501872969 is an equidigital number, since it uses as much as digits as its factorization.

21404501872969 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8709120, while the sum is 58.

The spelling of 21404501872969 in words is "twenty-one trillion, four hundred four billion, five hundred one million, eight hundred seventy-two thousand, nine hundred sixty-nine".