3181920 has 96 divisors (see below), whose sum is σ = 11467008. Its totient is φ = 726528.

The previous prime is 3181901. The next prime is 3181921. The reversal of 3181920 is 291813.

3181920 = 193² + 194² + ... + 255².

It is a tau number, because it is divible by the number of its divisors (96).

It is a super-2 number, since 2×3181920² = 20249229772800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3181921) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2887 + ... + 3833.

It is an arithmetic number, because the mean of its divisors is an integer number (119448).

Almost surely, 2^3181920 is an apocalyptic number.

3181920 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 3181920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (5733504).

3181920 is an abundant number, since it is smaller than the sum of its proper divisors (8285088).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

3181920 is a wasteful number, since it uses less digits than its factorization.

3181920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 972 (or 964 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 24.

The square root of 3181920 is about 1783.7937100461. The cubic root of 3181920 is about 147.0832052437.

The spelling of 3181920 in words is "three million, one hundred eighty-one thousand, nine hundred twenty".