26381640 has 32 divisors (see below), whose sum is σ = 79145280. Its totient is φ = 7035072.

The previous prime is 26381627. The next prime is 26381653. The reversal of 26381640 is 4618362.

It is an interprime number because it is at equal distance from previous prime (26381627) and next prime (26381653).

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 = 26381598 and 26381607.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 109804 + ... + 110043.

It is an arithmetic number, because the mean of its divisors is an integer number (2473290).

Almost surely, 2^26381640 is an apocalyptic number.

26381640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

26381640 is an abundant number, since it is smaller than the sum of its proper divisors (52763640).

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

26381640 is a wasteful number, since it uses less digits than its factorization.

26381640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 219861 (or 219857 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 30.

The square root of 26381640 is about 5136.3060656468. The cubic root of 26381640 is about 297.6920681437.

It can be divided in two parts, 2638 and 1640, that added together give a triangular number (4278 = T₉₂).

The spelling of 26381640 in words is "twenty-six million, three hundred eighty-one thousand, six hundred forty".