3921402561 has 16 divisors (see below), whose sum is σ = 5371756608. Its totient is φ = 2542708800.

The previous prime is 3921402557. The next prime is 3921402623. The reversal of 3921402561 is 1652041293.

It is not a de Polignac number, because 3921402561 - 2² = 3921402557 is a prime.

It is not an unprimeable number, because it can be changed into a prime (3921402061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 468826 + ... + 477116.

It is an arithmetic number, because the mean of its divisors is an integer number (335734788).

Almost surely, 2^3921402561 is an apocalyptic number.

It is an amenable number.

3921402561 is a deficient number, since it is larger than the sum of its proper divisors (1450354047).

3921402561 is a wasteful number, since it uses less digits than its factorization.

3921402561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12592.

The product of its (nonzero) digits is 12960, while the sum is 33.

The square root of 3921402561 is about 62621.1031601967. The cubic root of 3921402561 is about 1576.9350615491.

The spelling of 3921402561 in words is "three billion, nine hundred twenty-one million, four hundred two thousand, five hundred sixty-one".