81011438907 has 16 divisors (see below), whose sum is σ = 123975820800. Its totient is φ = 46093568832.

The previous prime is 81011438891. The next prime is 81011438923. The reversal of 81011438907 is 70983411018.

It is an interprime number because it is at equal distance from previous prime (81011438891) and next prime (81011438923).

It is not a de Polignac number, because 81011438907 - 2⁴ = 81011438891 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81011433907) 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, 8273407 + ... + 8283192.

It is an arithmetic number, because the mean of its divisors is an integer number (7748488800).

Almost surely, 2^81011438907 is an apocalyptic number.

81011438907 is a deficient number, since it is larger than the sum of its proper divisors (42964381893).

81011438907 is a wasteful number, since it uses less digits than its factorization.

81011438907 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16556842.

The product of its (nonzero) digits is 48384, while the sum is 42.

The spelling of 81011438907 in words is "eighty-one billion, eleven million, four hundred thirty-eight thousand, nine hundred seven".