820956487680 has 672 divisors, whose sum is σ = 3373096656384. Its totient is φ = 187631271936.

The previous prime is 820956487661. The next prime is 820956487699. The reversal of 820956487680 is 86784659028.

820956487680 is a `hidden beast` number, since 8 + 2 + 0 + 9 + 564 + 8 + 7 + 68 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (820956487661) and next prime (820956487699).

It is a tau number, because it is divible by the number of its divisors (672).

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 69667069 + ... + 69678851.

It is an arithmetic number, because the mean of its divisors is an integer number (5019489072).

Almost surely, 2^820956487680 is an apocalyptic number.

820956487680 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 820956487680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1686548328192).

820956487680 is an abundant number, since it is smaller than the sum of its proper divisors (2552140168704).

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

820956487680 is an equidigital number, since it uses as much as digits as its factorization.

820956487680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11836 (or 11800 counting only the distinct ones).

The product of its (nonzero) digits is 46448640, while the sum is 63.

The spelling of 820956487680 in words is "eight hundred twenty billion, nine hundred fifty-six million, four hundred eighty-seven thousand, six hundred eighty".