81400141 has 4 divisors (see below), whose sum is σ = 84025984. Its totient is φ = 78774300.

The previous prime is 81400093. The next prime is 81400171. The reversal of 81400141 is 14100418.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 81400141 - 2¹³ = 81391949 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 (81400171) 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, 1312875 + ... + 1312936.

It is an arithmetic number, because the mean of its divisors is an integer number (21006496).

Almost surely, 2^81400141 is an apocalyptic number.

It is an amenable number.

81400141 is a deficient number, since it is larger than the sum of its proper divisors (2625843).

81400141 is a wasteful number, since it uses less digits than its factorization.

81400141 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2625842.

The product of its (nonzero) digits is 128, while the sum is 19.

The square root of 81400141 is about 9022.2026689717. The cubic root of 81400141 is about 433.3861741612.

Adding to 81400141 its reverse (14100418), we get a palindrome (95500559).

The spelling of 81400141 in words is "eighty-one million, four hundred thousand, one hundred forty-one".