81714769920 has 1040 divisors, whose sum is σ = 347095001088. Its totient is φ = 17995530240.

The previous prime is 81714769919. The next prime is 81714769921. The reversal of 81714769920 is 2996741718.

81714769920 is a `hidden beast` number, since 81 + 7 + 1 + 476 + 9 + 92 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (81714769919) and next prime (81714769921).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81714769921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 359976847 + ... + 359977073.

Almost surely, 2^81714769920 is an apocalyptic number.

81714769920 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81714769920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (173547500544).

81714769920 is an abundant number, since it is smaller than the sum of its proper divisors (265380231168).

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

81714769920 is a wasteful number, since it uses less digits than its factorization.

81714769920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 306 (or 275 counting only the distinct ones).

The product of its (nonzero) digits is 1524096, while the sum is 54.

The spelling of 81714769920 in words is "eighty-one billion, seven hundred fourteen million, seven hundred sixty-nine thousand, nine hundred twenty".