3821721256942 has 16 divisors (see below), whose sum is σ = 5741255265840. Its totient is φ = 1907971676992.

The previous prime is 3821721256907. The next prime is 3821721256949. The reversal of 3821721256942 is 2496521271283.

It is a self number, because there is not a number n which added to its sum of digits gives 3821721256942.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3821721256949) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2979813 + ... + 4064815.

It is an arithmetic number, because the mean of its divisors is an integer number (358828454115).

Almost surely, 2^{3821721256942} is an apocalyptic number.

3821721256942 is a deficient number, since it is larger than the sum of its proper divisors (1919534008898).

3821721256942 is a wasteful number, since it uses less digits than its factorization.

3821721256942 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1087667.

The product of its digits is 2903040, while the sum is 52.

The spelling of 3821721256942 in words is "three trillion, eight hundred twenty-one billion, seven hundred twenty-one million, two hundred fifty-six thousand, nine hundred forty-two".