71660699136 has 640 divisors, whose sum is σ = 248584089600. Its totient is φ = 20185251840.

The previous prime is 71660699053. The next prime is 71660699137. The reversal of 71660699136 is 63199606617.

71660699136 is a `hidden beast` number, since 7 + 16 + 606 + 9 + 9 + 13 + 6 = 666.

It is a super-2 number, since 2×71660699136² (a number of 23 digits) contains 22 as substring.

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 (71660699137) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 105850030 + ... + 105850706.

It is an arithmetic number, because the mean of its divisors is an integer number (388412640).

Almost surely, 2^71660699136 is an apocalyptic number.

71660699136 is a gapful number since it is divisible by the number (76) 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 71660699136, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (124292044800).

71660699136 is an abundant number, since it is smaller than the sum of its proper divisors (176923390464).

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

71660699136 is a wasteful number, since it uses less digits than its factorization.

71660699136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 767 (or 745 counting only the distinct ones).

The product of its (nonzero) digits is 2204496, while the sum is 54.

The spelling of 71660699136 in words is "seventy-one billion, six hundred sixty million, six hundred ninety-nine thousand, one hundred thirty-six".