71221272 has 64 divisors (see below), whose sum is σ = 188400000. Its totient is φ = 22374144.

The previous prime is 71221259. The next prime is 71221277. The reversal of 71221272 is 27212217.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71221277) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 142479 + ... + 142977.

It is an arithmetic number, because the mean of its divisors is an integer number (2943750).

Almost surely, 2^71221272 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 71221272, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (94200000).

71221272 is an abundant number, since it is smaller than the sum of its proper divisors (117178728).

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

71221272 is a wasteful number, since it uses less digits than its factorization.

71221272 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 840 (or 836 counting only the distinct ones).

The product of its digits is 784, while the sum is 24.

The square root of 71221272 is about 8439.2696366451. The cubic root of 71221272 is about 414.5114917684.

Adding to 71221272 its reverse (27212217), we get a palindrome (98433489).

The spelling of 71221272 in words is "seventy-one million, two hundred twenty-one thousand, two hundred seventy-two".