81405262 has 16 divisors (see below), whose sum is σ = 127040400. Its totient is φ = 39074560.

The previous prime is 81405229. The next prime is 81405301. The reversal of 81405262 is 26250418.

It is a self number, because there is not a number n which added to its sum of digits gives 81405262.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6462 + ... + 14302.

It is an arithmetic number, because the mean of its divisors is an integer number (7940025).

Almost surely, 2^81405262 is an apocalyptic number.

81405262 is a deficient number, since it is larger than the sum of its proper divisors (45635138).

81405262 is a wasteful number, since it uses less digits than its factorization.

81405262 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8051.

The product of its (nonzero) digits is 3840, while the sum is 28.

The square root of 81405262 is about 9022.4864643844. The cubic root of 81405262 is about 433.3952622865.

The spelling of 81405262 in words is "eighty-one million, four hundred five thousand, two hundred sixty-two".