21004462669 has 2 divisors, whose sum is σ = 21004462670. Its totient is φ = 21004462668.

The previous prime is 21004462663. The next prime is 21004462673. The reversal of 21004462669 is 96626440012.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16831948644 + 4172514025 = 129738^2 + 64595^2 .

It is a cyclic number.

It is not a de Polignac number, because 21004462669 - 2⁷ = 21004462541 is a prime.

It is a super-2 number, since 2×21004462669² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21004462663) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10502231334 + 10502231335.

It is an arithmetic number, because the mean of its divisors is an integer number (10502231335).

Almost surely, 2^21004462669 is an apocalyptic number.

It is an amenable number.

21004462669 is a deficient number, since it is larger than the sum of its proper divisors (1).

21004462669 is an equidigital number, since it uses as much as digits as its factorization.

21004462669 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 124416, while the sum is 40.

It can be divided in two parts, 2100 and 4462669, that added together give a square (4464769 = 2113²).

The spelling of 21004462669 in words is "twenty-one billion, four million, four hundred sixty-two thousand, six hundred sixty-nine".