39664469820 has 192 divisors, whose sum is σ = 114406096896. Its totient is φ = 10265149440.

The previous prime is 39664469797. The next prime is 39664469827. The reversal of 39664469820 is 2896446693.

It is a happy number.

It is a super-2 number, since 2×39664469820² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (39664469827) 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, 76131160 + ... + 76131680.

It is an arithmetic number, because the mean of its divisors is an integer number (595865088).

Almost surely, 2^39664469820 is an apocalyptic number.

39664469820 is a gapful number since it is divisible by the number (30) 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 39664469820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (57203048448).

39664469820 is an abundant number, since it is smaller than the sum of its proper divisors (74741627076).

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

39664469820 is a wasteful number, since it uses less digits than its factorization.

39664469820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 860 (or 858 counting only the distinct ones).

The product of its (nonzero) digits is 13436928, while the sum is 57.

The spelling of 39664469820 in words is "thirty-nine billion, six hundred sixty-four million, four hundred sixty-nine thousand, eight hundred twenty".