81261555954 has 16 divisors (see below), whose sum is σ = 163052506848. Its totient is φ = 26998952832.

The previous prime is 81261555937. The next prime is 81261555971. The reversal of 81261555954 is 45955516218.

It is an interprime number because it is at equal distance from previous prime (81261555937) and next prime (81261555971).

It is a junction number, because it is equal to n+sod(n) for n = 81261555897 and 81261555906.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22056127 + ... + 22059810.

It is an arithmetic number, because the mean of its divisors is an integer number (10190781678).

Almost surely, 2^81261555954 is an apocalyptic number.

81261555954 is an abundant number, since it is smaller than the sum of its proper divisors (81790950894).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81261555954 is a wasteful number, since it uses less digits than its factorization.

81261555954 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44116249.

The product of its digits is 2160000, while the sum is 51.

The spelling of 81261555954 in words is "eighty-one billion, two hundred sixty-one million, five hundred fifty-five thousand, nine hundred fifty-four".