3999023421120 has 2520 divisors, whose sum is σ = 18527326570368. Its totient is φ = 815173632000.

The previous prime is 3999023421101. The next prime is 3999023421203. The reversal of 3999023421120 is 211243209993.

It is a happy number.

3999023421120 is a `hidden beast` number, since 399 + 9 + 0 + 23 + 4 + 211 + 20 = 666.

It is a tau number, because it is divible by the number of its divisors (2520).

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

It is an unprimeable number.

It is a polite number, since it can be written in 359 ways as a sum of consecutive naturals, for example, 6653948820 + ... + 6653949420.

Almost surely, 2^{3999023421120} is an apocalyptic number.

3999023421120 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 3999023421120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (9263663285184).

3999023421120 is an abundant number, since it is smaller than the sum of its proper divisors (14528303149248).

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

3999023421120 is a wasteful number, since it uses less digits than its factorization.

3999023421120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 701 (or 662 counting only the distinct ones).

The product of its (nonzero) digits is 209952, while the sum is 45.

The spelling of 3999023421120 in words is "three trillion, nine hundred ninety-nine billion, twenty-three million, four hundred twenty-one thousand, one hundred twenty".