7211581440 has 320 divisors, whose sum is σ = 26575084800. Its totient is φ = 1635778560.

The previous prime is 7211581411. The next prime is 7211581477. The reversal of 7211581440 is 441851127.

It is a tau number, because it is divible by the number of its divisors (320).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 55050175 + ... + 55050305.

It is an arithmetic number, because the mean of its divisors is an integer number (83047140).

Almost surely, 2^7211581440 is an apocalyptic number.

7211581440 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 7211581440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13287542400).

7211581440 is an abundant number, since it is smaller than the sum of its proper divisors (19363503360).

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

7211581440 is an frugal number, since it uses more digits than its factorization.

7211581440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 184 (or 148 counting only the distinct ones).

The product of its (nonzero) digits is 8960, while the sum is 33.

The square root of 7211581440 is about 84921.0306107975. The cubic root of 7211581440 is about 1932.0135624817.

The spelling of 7211581440 in words is "seven billion, two hundred eleven million, five hundred eighty-one thousand, four hundred forty".