71667540 has 144 divisors (see below), whose sum is σ = 259354368. Its totient is φ = 15662592.

The previous prime is 71667451. The next prime is 71667569. The reversal of 71667540 is 4576617.

71667540 is digitally balanced in base 9, because in such base it contains all the possibile digits an equal number of times.

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

71667540 is strictly pandigital in base 9.

It is a junction number, because it is equal to n+sod(n) for n = 71667495 and 71667504.

It is a congruent number.

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, 27744 + ... + 30216.

It is an arithmetic number, because the mean of its divisors is an integer number (1801072).

Almost surely, 2^71667540 is an apocalyptic number.

71667540 is a gapful number since it is divisible by the number (70) 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 71667540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (129677184).

71667540 is an abundant number, since it is smaller than the sum of its proper divisors (187686828).

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

71667540 is a wasteful number, since it uses less digits than its factorization.

71667540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2518 (or 2513 counting only the distinct ones).

The product of its (nonzero) digits is 35280, while the sum is 36.

The square root of 71667540 is about 8465.6683138427. The cubic root of 71667540 is about 415.3754573796.

It can be divided in two parts, 7166 and 7540, that added together give a triangular number (14706 = T₁₇₁).

The spelling of 71667540 in words is "seventy-one million, six hundred sixty-seven thousand, five hundred forty".