26820432981 has 6 divisors (see below), whose sum is σ = 38740625430. Its totient is φ = 17880288648.

The previous prime is 26820432937. The next prime is 26820432997. The reversal of 26820432981 is 18923402862.

It can be written as a sum of positive squares in only one way, i.e., 19046484081 + 7773948900 = 138009^2 + 88170^2 .

It is not a de Polignac number, because 26820432981 - 2¹⁹ = 26819908693 is a prime.

It is a super-2 number, since 2×26820432981² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (26820432901) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1490024046 + ... + 1490024063.

It is an arithmetic number, because the mean of its divisors is an integer number (6456770905).

Almost surely, 2^26820432981 is an apocalyptic number.

It is an amenable number.

26820432981 is a deficient number, since it is larger than the sum of its proper divisors (11920192449).

26820432981 is a wasteful number, since it uses less digits than its factorization.

26820432981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2980048115 (or 2980048112 counting only the distinct ones).

The product of its (nonzero) digits is 331776, while the sum is 45.

The spelling of 26820432981 in words is "twenty-six billion, eight hundred twenty million, four hundred thirty-two thousand, nine hundred eighty-one".