31987076220 has 144 divisors (see below), whose sum is σ = 107845631712. Its totient is φ = 7608107520.

The previous prime is 31987076197. The next prime is 31987076243. The reversal of 31987076220 is 2267078913.

31987076220 is a `hidden beast` number, since 3 + 19 + 8 + 7 + 0 + 7 + 622 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (31987076197) and next prime (31987076243).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 47467 + ... + 257346.

It is an arithmetic number, because the mean of its divisors is an integer number (748927998).

Almost surely, 2^31987076220 is an apocalyptic number.

31987076220 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 31987076220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (53922815856).

31987076220 is an abundant number, since it is smaller than the sum of its proper divisors (75858555492).

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

31987076220 is a wasteful number, since it uses less digits than its factorization.

31987076220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 304892 (or 304887 counting only the distinct ones).

The product of its (nonzero) digits is 254016, while the sum is 45.

The spelling of 31987076220 in words is "thirty-one billion, nine hundred eighty-seven million, seventy-six thousand, two hundred twenty".