71263921 has 4 divisors (see below), whose sum is σ = 72432244. Its totient is φ = 70095600.

The previous prime is 71263901. The next prime is 71263931. The reversal of 71263921 is 12936217.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12936217 = 7 ⋅1848031.

It can be written as a sum of positive squares in 2 ways, for example, as 5475600 + 65788321 = 2340^2 + 8111^2 .

It is a cyclic number.

It is not a de Polignac number, because 71263921 - 2⁷ = 71263793 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (71263901) 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, 584070 + ... + 584191.

It is an arithmetic number, because the mean of its divisors is an integer number (18108061).

Almost surely, 2^71263921 is an apocalyptic number.

It is an amenable number.

71263921 is a deficient number, since it is larger than the sum of its proper divisors (1168323).

71263921 is a wasteful number, since it uses less digits than its factorization.

71263921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1168322.

The product of its digits is 4536, while the sum is 31.

The square root of 71263921 is about 8441.7960766652. The cubic root of 71263921 is about 414.5942150546.

The spelling of 71263921 in words is "seventy-one million, two hundred sixty-three thousand, nine hundred twenty-one".