81795428001 has 27 divisors (see below), whose sum is σ = 137448668721. Its totient is φ = 46736812584.

The previous prime is 81795427993. The next prime is 81795428009. The reversal of 81795428001 is 10082459718.

The square root of 81795428001 is 285999.

It is a perfect power (a square), and thus also a powerful number.

It is an interprime number because it is at equal distance from previous prime (81795427993) and next prime (81795428009).

It is not a de Polignac number, because 81795428001 - 2³ = 81795427993 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81795428009) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 5999170 + ... + 6012788.

Almost surely, 2^81795428001 is an apocalyptic number.

81795428001 is the 285999-th square number.

81795428001 is the 143000-th centered octagonal number.

It is an amenable number.

81795428001 is a deficient number, since it is larger than the sum of its proper divisors (55653240720).

81795428001 is an frugal number, since it uses more digits than its factorization.

81795428001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27258 (or 13629 counting only the distinct ones).

The product of its (nonzero) digits is 161280, while the sum is 45.

It can be divided in two parts, 81795 and 428001, that added together give a square (509796 = 714²).

The spelling of 81795428001 in words is "eighty-one billion, seven hundred ninety-five million, four hundred twenty-eight thousand, one".