71142840 has 128 divisors (see below), whose sum is σ = 249696000. Its totient is φ = 17967744.

The previous prime is 71142833. The next prime is 71142853. The reversal of 71142840 is 4824117.

It is a super-2 number, since 2×71142840² = 10122607366531200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 18787 + ... + 22253.

It is an arithmetic number, because the mean of its divisors is an integer number (1950750).

Almost surely, 2^71142840 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 71142840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (124848000).

71142840 is an abundant number, since it is smaller than the sum of its proper divisors (178553160).

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

71142840 is a wasteful number, since it uses less digits than its factorization.

71142840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3506 (or 3496 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 27.

The square root of 71142840 is about 8434.6215089949. The cubic root of 71142840 is about 414.3592764452.

Adding to 71142840 its reverse (4824117), we get a palindrome (75966957).

The spelling of 71142840 in words is "seventy-one million, one hundred forty-two thousand, eight hundred forty".