387432721920 has 160 divisors (see below), whose sum is σ = 1250152092288. Its totient is φ = 102349611008.

The previous prime is 387432721901. The next prime is 387432721937. The reversal of 387432721920 is 29127234783.

It is a tau number, because it is divible by the number of its divisors (160).

It is a super-2 number, since 2×387432721920² (a number of 24 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 387432721920.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 586027 + ... + 1057493.

Almost surely, 2^387432721920 is an apocalyptic number.

387432721920 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 387432721920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (625076046144).

387432721920 is an abundant number, since it is smaller than the sum of its proper divisors (862719370368).

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

387432721920 is a wasteful number, since it uses less digits than its factorization.

387432721920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 471600 (or 471584 counting only the distinct ones).

The product of its (nonzero) digits is 1016064, while the sum is 48.

The spelling of 387432721920 in words is "three hundred eighty-seven billion, four hundred thirty-two million, seven hundred twenty-one thousand, nine hundred twenty".