4001961 has 8 divisors (see below), whose sum is σ = 5352480. Its totient is φ = 2659712.

The previous prime is 4001947. The next prime is 4001999. The reversal of 4001961 is 1691004.

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

It is a cyclic number.

It is not a de Polignac number, because 4001961 - 2¹⁰ = 4000937 is a prime.

It is not an unprimeable number, because it can be changed into a prime (4001461) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 831 + ... + 2948.

It is an arithmetic number, because the mean of its divisors is an integer number (669060).

Almost surely, 2^4001961 is an apocalyptic number.

It is an amenable number.

4001961 is a deficient number, since it is larger than the sum of its proper divisors (1350519).

4001961 is a wasteful number, since it uses less digits than its factorization.

4001961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4135.

The product of its (nonzero) digits is 216, while the sum is 21.

The square root of 4001961 is about 2000.4901899285. The cubic root of 4001961 is about 158.7660417377.

Adding to 4001961 its reverse (1691004), we get a palindrome (5692965).

The spelling of 4001961 in words is "four million, one thousand, nine hundred sixty-one".