71042640 has 40 divisors (see below), whose sum is σ = 220232928. Its totient is φ = 18944640.

The previous prime is 71042617. The next prime is 71042689. The reversal of 71042640 is 4624017.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 71042640.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 147766 + ... + 148245.

Almost surely, 2^71042640 is an apocalyptic number.

It is an amenable number.

71042640 is an abundant number, since it is smaller than the sum of its proper divisors (149190288).

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

71042640 is a wasteful number, since it uses less digits than its factorization.

71042640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 296027 (or 296021 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 24.

The square root of 71042640 is about 8428.6796118965. The cubic root of 71042640 is about 414.1646524703.

Adding to 71042640 its reverse (4624017), we get a palindrome (75666657).

The spelling of 71042640 in words is "seventy-one million, forty-two thousand, six hundred forty".