81177429869 has 8 divisors (see below), whose sum is σ = 81410373120. Its totient is φ = 80944551216.

The previous prime is 81177429863. The next prime is 81177429887. The reversal of 81177429869 is 96892477118.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81177429869 is a prime.

It is a super-2 number, since 2×81177429869² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81177429863) 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, 3717467 + ... + 3739239.

It is an arithmetic number, because the mean of its divisors is an integer number (10176296640).

Almost surely, 2^81177429869 is an apocalyptic number.

It is an amenable number.

81177429869 is a deficient number, since it is larger than the sum of its proper divisors (232943251).

81177429869 is a wasteful number, since it uses less digits than its factorization.

81177429869 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32299.

The product of its digits is 12192768, while the sum is 62.

The spelling of 81177429869 in words is "eighty-one billion, one hundred seventy-seven million, four hundred twenty-nine thousand, eight hundred sixty-nine".