26921640 has 64 divisors (see below), whose sum is σ = 83381760. Its totient is φ = 6946560.

The previous prime is 26921627. The next prime is 26921669. The reversal of 26921640 is 4612962.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 26921598 and 26921607.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 102 + ... + 7338.

It is an arithmetic number, because the mean of its divisors is an integer number (1302840).

Almost surely, 2^26921640 is an apocalyptic number.

26921640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 26921640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41690880).

26921640 is an abundant number, since it is smaller than the sum of its proper divisors (56460120).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

26921640 is a wasteful number, since it uses less digits than its factorization.

26921640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7282 (or 7278 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 30.

The square root of 26921640 is about 5188.6067494078. The cubic root of 26921640 is about 299.7094965611.

The spelling of 26921640 in words is "twenty-six million, nine hundred twenty-one thousand, six hundred forty".