18831961 has 8 divisors (see below), whose sum is σ = 19080000. Its totient is φ = 18585840.

The previous prime is 18831959. The next prime is 18832003. The reversal of 18831961 is 16913881.

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 18831961 - 2¹ = 18831959 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18831961.

It is not an unprimeable number, because it can be changed into a prime (18831931) 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, 31140 + ... + 31738.

It is an arithmetic number, because the mean of its divisors is an integer number (2385000).

Almost surely, 2^18831961 is an apocalyptic number.

It is an amenable number.

18831961 is a deficient number, since it is larger than the sum of its proper divisors (248039).

18831961 is a wasteful number, since it uses less digits than its factorization.

18831961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 959.

The product of its digits is 10368, while the sum is 37.

The square root of 18831961 is about 4339.5807401176. The cubic root of 18831961 is about 266.0511754478.

It can be divided in two parts, 1883 and 1961, that added together give a square (3844 = 62²).

The spelling of 18831961 in words is "eighteen million, eight hundred thirty-one thousand, nine hundred sixty-one".