381920987 has 8 divisors (see below), whose sum is σ = 439622400. Its totient is φ = 325004904.

The previous prime is 381920977. The next prime is 381920989. The reversal of 381920987 is 789029183.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 381920987 - 2¹⁶ = 381855451 is a prime.

It is a super-2 number, since 2×381920987² = 291727280622108338, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (381920989) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 195287 + ... + 197232.

It is an arithmetic number, because the mean of its divisors is an integer number (54952800).

Almost surely, 2^381920987 is an apocalyptic number.

381920987 is a deficient number, since it is larger than the sum of its proper divisors (57701413).

381920987 is a wasteful number, since it uses less digits than its factorization.

381920987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 392665.

The product of its (nonzero) digits is 217728, while the sum is 47.

The square root of 381920987 is about 19542.7988527744. The cubic root of 381920987 is about 725.5341205570.

The spelling of 381920987 in words is "three hundred eighty-one million, nine hundred twenty thousand, nine hundred eighty-seven".