71401520221 has 4 divisors (see below), whose sum is σ = 71856307132. Its totient is φ = 70946733312.

The previous prime is 71401520173. The next prime is 71401520227. The reversal of 71401520221 is 12202510417.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 16284567321 + 55116952900 = 127611^2 + 234770^2 .

It is a cyclic number.

It is not a de Polignac number, because 71401520221 - 2³⁵ = 37041781853 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71401520227) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 227393220 + ... + 227393533.

It is an arithmetic number, because the mean of its divisors is an integer number (17964076783).

Almost surely, 2^71401520221 is an apocalyptic number.

It is an amenable number.

71401520221 is a deficient number, since it is larger than the sum of its proper divisors (454786911).

71401520221 is a wasteful number, since it uses less digits than its factorization.

71401520221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 454786910.

The product of its (nonzero) digits is 1120, while the sum is 25.

The spelling of 71401520221 in words is "seventy-one billion, four hundred one million, five hundred twenty thousand, two hundred twenty-one".