71273621 has 4 divisors (see below), whose sum is σ = 73012044. Its totient is φ = 69535200.

The previous prime is 71273611. The next prime is 71273627. The reversal of 71273621 is 12637217.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12637217 = 3083 ⋅4099.

It can be written as a sum of positive squares in 2 ways, for example, as 20151121 + 51122500 = 4489^2 + 7150^2 .

It is a cyclic number.

It is not a de Polignac number, because 71273621 - 2²² = 67079317 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 (71273627) 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, 869150 + ... + 869231.

It is an arithmetic number, because the mean of its divisors is an integer number (18253011).

Almost surely, 2^71273621 is an apocalyptic number.

It is an amenable number.

71273621 is a deficient number, since it is larger than the sum of its proper divisors (1738423).

71273621 is a wasteful number, since it uses less digits than its factorization.

71273621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1738422.

The product of its digits is 3528, while the sum is 29.

The square root of 71273621 is about 8442.3705794048. The cubic root of 71273621 is about 414.6130248599.

The spelling of 71273621 in words is "seventy-one million, two hundred seventy-three thousand, six hundred twenty-one".