81305974264 has 32 divisors (see below), whose sum is σ = 155087618400. Its totient is φ = 39950478720.

The previous prime is 81305974261. The next prime is 81305974291. The reversal of 81305974264 is 46247950318.

It is a happy number.

It is a super-2 number, since 2×81305974264² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81305974261) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 470517 + ... + 619675.

It is an arithmetic number, because the mean of its divisors is an integer number (4846488075).

It is a 1-persistent number, because it is pandigital, but 2⋅81305974264 = 162611948528 is not.

Almost surely, 2^81305974264 is an apocalyptic number.

It is an amenable number.

81305974264 is a deficient number, since it is larger than the sum of its proper divisors (73781644136).

81305974264 is a wasteful number, since it uses less digits than its factorization.

81305974264 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 150343 (or 150339 counting only the distinct ones).

The product of its (nonzero) digits is 1451520, while the sum is 49.

The spelling of 81305974264 in words is "eighty-one billion, three hundred five million, nine hundred seventy-four thousand, two hundred sixty-four".