26671667021 has 4 divisors (see below), whose sum is σ = 26672017692. Its totient is φ = 26671316352.

The previous prime is 26671667003. The next prime is 26671667041. The reversal of 26671667021 is 12076617662.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 15090894025 + 11580772996 = 122845^2 + 107614^2 .

It is a cyclic number.

It is not a de Polignac number, because 26671667021 - 2¹⁰ = 26671665997 is a prime.

It is a super-2 number, since 2×26671667021² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (26671667041) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8036 + ... + 231101.

It is an arithmetic number, because the mean of its divisors is an integer number (6668004423).

Almost surely, 2^26671667021 is an apocalyptic number.

It is an amenable number.

26671667021 is a deficient number, since it is larger than the sum of its proper divisors (350671).

26671667021 is a wasteful number, since it uses less digits than its factorization.

26671667021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 350670.

The product of its (nonzero) digits is 254016, while the sum is 44.

The spelling of 26671667021 in words is "twenty-six billion, six hundred seventy-one million, six hundred sixty-seven thousand, twenty-one".