71428561 has 8 divisors (see below), whose sum is σ = 72504320. Its totient is φ = 70357248.

The previous prime is 71428559. The next prime is 71428571. The reversal of 71428561 is 16582417.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 71428561 - 2¹ = 71428559 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (71428531) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 44800 + ... + 46366.

It is an arithmetic number, because the mean of its divisors is an integer number (9063040).

Almost surely, 2^71428561 is an apocalyptic number.

71428561 is the 4880-th hex number.

It is an amenable number.

71428561 is a deficient number, since it is larger than the sum of its proper divisors (1075759).

71428561 is a wasteful number, since it uses less digits than its factorization.

71428561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2223.

The product of its digits is 13440, while the sum is 34.

The square root of 71428561 is about 8451.5419303225. The cubic root of 71428561 is about 414.9132464907.

The spelling of 71428561 in words is "seventy-one million, four hundred twenty-eight thousand, five hundred sixty-one".