71221431138 has 32 divisors (see below), whose sum is σ = 167345462592. Its totient is φ = 19922078400.

The previous prime is 71221431121. The next prime is 71221431143. The reversal of 71221431138 is 83113412217.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a junction number, because it is equal to n+sod(n) for n = 71221431099 and 71221431108.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 41503473 + ... + 41505188.

It is an arithmetic number, because the mean of its divisors is an integer number (5229545706).

Almost surely, 2^71221431138 is an apocalyptic number.

71221431138 is a gapful number since it is divisible by the number (78) formed by its first and last digit.

71221431138 is an abundant number, since it is smaller than the sum of its proper divisors (96124031454).

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

71221431138 is a wasteful number, since it uses less digits than its factorization.

71221431138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83008690.

The product of its digits is 8064, while the sum is 33.

The spelling of 71221431138 in words is "seventy-one billion, two hundred twenty-one million, four hundred thirty-one thousand, one hundred thirty-eight".