1284000121656 has 192 divisors, whose sum is σ = 4114832529600. Its totient is φ = 353905219584.

The previous prime is 1284000121639. The next prime is 1284000121673. The reversal of 1284000121656 is 6561210004821.

It is a happy number.

1284000121656 is a `hidden beast` number, since 128 + 400 + 0 + 121 + 6 + 5 + 6 = 666.

It is an interprime number because it is at equal distance from previous prime (1284000121639) and next prime (1284000121673).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 1284000121656.

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, 17400070 + ... + 17473706.

It is an arithmetic number, because the mean of its divisors is an integer number (21431419425).

Almost surely, 2^{1284000121656} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1284000121656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2057416264800).

1284000121656 is an abundant number, since it is smaller than the sum of its proper divisors (2830832407944).

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

1284000121656 is a wasteful number, since it uses less digits than its factorization.

1284000121656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74878 (or 74871 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 36.

The spelling of 1284000121656 in words is "one trillion, two hundred eighty-four billion, one hundred twenty-one thousand, six hundred fifty-six".