71621431 has 16 divisors (see below), whose sum is σ = 86464000. Its totient is φ = 57954528.

The previous prime is 71621419. The next prime is 71621437. The reversal of 71621431 is 13412617.

It is a cyclic number.

It is not a de Polignac number, because 71621431 - 2⁵ = 71621399 is a prime.

It is a super-2 number, since 2×71621431² = 10259258756975522, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 71621396 and 71621405.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71621437) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 45646 + ... + 47188.

It is an arithmetic number, because the mean of its divisors is an integer number (5404000).

Almost surely, 2^71621431 is an apocalyptic number.

71621431 is a deficient number, since it is larger than the sum of its proper divisors (14842569).

71621431 is a wasteful number, since it uses less digits than its factorization.

71621431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1918.

The product of its digits is 1008, while the sum is 25.

The square root of 71621431 is about 8462.9445821180. The cubic root of 71621431 is about 415.2863577405.

The spelling of 71621431 in words is "seventy-one million, six hundred twenty-one thousand, four hundred thirty-one".