71490781440 has 1440 divisors, whose sum is σ = 299163110400. Its totient is φ = 16164126720.

The previous prime is 71490781421. The next prime is 71490781441. The reversal of 71490781440 is 4418709417.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (1440).

It is a super-2 number, since 2×71490781440² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (71490781441) by changing a digit.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 1211708131 + ... + 1211708189.

It is an arithmetic number, because the mean of its divisors is an integer number (207752160).

Almost surely, 2^71490781440 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 71490781440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (149581555200).

71490781440 is an abundant number, since it is smaller than the sum of its proper divisors (227672328960).

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

71490781440 is a wasteful number, since it uses less digits than its factorization.

71490781440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 165 (or 142 counting only the distinct ones).

The product of its (nonzero) digits is 225792, while the sum is 45.

The spelling of 71490781440 in words is "seventy-one billion, four hundred ninety million, seven hundred eighty-one thousand, four hundred forty".