26642643393840 has 80 divisors (see below), whose sum is σ = 82608453408096. Its totient is φ = 7103306291200.

The previous prime is 26642643393833. The next prime is 26642643393893. The reversal of 26642643393840 is 4839334624662.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-2 number, since 2×26642643393840² (a number of 28 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (60).

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, 9704691 + ... + 12143570.

Almost surely, 2^{26642643393840} is an apocalyptic number.

26642643393840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

26642643393840 is an abundant number, since it is smaller than the sum of its proper divisors (55965810014256).

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

26642643393840 is a wasteful number, since it uses less digits than its factorization.

26642643393840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21853358 (or 21853352 counting only the distinct ones).

The product of its (nonzero) digits is 107495424, while the sum is 60.

The spelling of 26642643393840 in words is "twenty-six trillion, six hundred forty-two billion, six hundred forty-three million, three hundred ninety-three thousand, eight hundred forty".