806138640 has 240 divisors, whose sum is σ = 2912277888. Its totient is φ = 199102464.

The previous prime is 806138617. The next prime is 806138651. The reversal of 806138640 is 46831608.

It is a happy number.

806138640 is a `hidden beast` number, since 8 + 0 + 6 + 1 + 3 + 8 + 640 = 666.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 806138595 and 806138604.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 819589 + ... + 820571.

Almost surely, 2^806138640 is an apocalyptic number.

806138640 is a gapful number since it is divisible by the number (80) 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 806138640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1456138944).

806138640 is an abundant number, since it is smaller than the sum of its proper divisors (2106139248).

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

806138640 is a wasteful number, since it uses less digits than its factorization.

806138640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1086 (or 1077 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 36.

The square root of 806138640 is about 28392.5807210264. The cubic root of 806138640 is about 930.6861395075.

It can be divided in two parts, 80613 and 8640, that added together give a triangular number (89253 = T₄₂₂).

The spelling of 806138640 in words is "eight hundred six million, one hundred thirty-eight thousand, six hundred forty".