6215807681 has 4 divisors (see below), whose sum is σ = 6360361392. Its totient is φ = 6071253972.

The previous prime is 6215807659. The next prime is 6215807761. The reversal of 6215807681 is 1867085126.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1867085126 = 2 ⋅933542563.

It is a cyclic number.

It is not a de Polignac number, because 6215807681 - 2¹⁸ = 6215545537 is a prime.

It is a super-2 number, since 2×6215807681² = 77272530254357195522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6215807651) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 72276791 + ... + 72276876.

It is an arithmetic number, because the mean of its divisors is an integer number (1590090348).

Almost surely, 2^6215807681 is an apocalyptic number.

It is an amenable number.

6215807681 is a deficient number, since it is larger than the sum of its proper divisors (144553711).

6215807681 is a wasteful number, since it uses less digits than its factorization.

6215807681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 144553710.

The product of its (nonzero) digits is 161280, while the sum is 44.

The square root of 6215807681 is about 78840.3937141362. The cubic root of 6215807681 is about 1838.6505229058.

The spelling of 6215807681 in words is "six billion, two hundred fifteen million, eight hundred seven thousand, six hundred eighty-one".