26660421 has 30 divisors (see below), whose sum is σ = 40964550. Its totient is φ = 17278704.

The previous prime is 26660411. The next prime is 26660449. The reversal of 26660421 is 12406662.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 17892900 + 8767521 = 4230^2 + 2961^2 .

It is not a de Polignac number, because 26660421 - 2⁹ = 26659909 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (26660411) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 178855 + ... + 179003.

It is an arithmetic number, because the mean of its divisors is an integer number (1365485).

Almost surely, 2^26660421 is an apocalyptic number.

It is an amenable number.

26660421 is a deficient number, since it is larger than the sum of its proper divisors (14304129).

26660421 is an equidigital number, since it uses as much as digits as its factorization.

26660421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 255 (or 199 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The square root of 26660421 is about 5163.3730254554. The cubic root of 26660421 is about 298.7369901491.

The spelling of 26660421 in words is "twenty-six million, six hundred sixty thousand, four hundred twenty-one".