81341421 has 32 divisors (see below), whose sum is σ = 127622400. Its totient is φ = 46061568.

The previous prime is 81341419. The next prime is 81341431. The reversal of 81341421 is 12414318.

It is not a de Polignac number, because 81341421 - 2¹ = 81341419 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 81341391 and 81341400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81341431) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 140685 + ... + 141261.

It is an arithmetic number, because the mean of its divisors is an integer number (3988200).

Almost surely, 2^81341421 is an apocalyptic number.

It is an amenable number.

81341421 is a deficient number, since it is larger than the sum of its proper divisors (46280979).

81341421 is a wasteful number, since it uses less digits than its factorization.

81341421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 738 (or 724 counting only the distinct ones).

The product of its digits is 768, while the sum is 24.

The square root of 81341421 is about 9018.9478876419. The cubic root of 81341421 is about 433.2819378229.

Adding to 81341421 its reverse (12414318), we get a palindrome (93755739).

The spelling of 81341421 in words is "eighty-one million, three hundred forty-one thousand, four hundred twenty-one".