71404561 has 8 divisors (see below), whose sum is σ = 73465704. Its totient is φ = 69350400.

The previous prime is 71404559. The next prime is 71404589. The reversal of 71404561 is 16540417.

71404561 is nontrivially palindromic in base 2.

It can be written as a sum of positive squares in 4 ways, for example, as 55651600 + 15752961 = 7460^2 + 3969^2 .

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 71404561 - 2¹ = 71404559 is a prime.

It is a super-2 number, since 2×71404561² = 10197222663205442, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (71404511) 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, 24561 + ... + 27313.

It is an arithmetic number, because the mean of its divisors is an integer number (9183213).

Almost surely, 2^71404561 is an apocalyptic number.

It is an amenable number.

71404561 is a deficient number, since it is larger than the sum of its proper divisors (2061143).

71404561 is a wasteful number, since it uses less digits than its factorization.

71404561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3491.

The product of its (nonzero) digits is 3360, while the sum is 28.

The square root of 71404561 is about 8450.1219517827. The cubic root of 71404561 is about 414.8667709946.

Adding to 71404561 its reverse (16540417), we get a palindrome (87944978).

The spelling of 71404561 in words is "seventy-one million, four hundred four thousand, five hundred sixty-one".