1881972 has 36 divisors (see below), whose sum is σ = 4840836. Its totient is φ = 616320.

The previous prime is 1881961. The next prime is 1881983. The reversal of 1881972 is 2791881.

It is an interprime number because it is at equal distance from previous prime (1881961) and next prime (1881983).

It can be written as a sum of positive squares in 2 ways, for example, as 853776 + 1028196 = 924^2 + 1014^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1768 + ... + 2624.

2^1881972 is an apocalyptic number.

1881972 is a gapful number since it is divisible by the number (12) 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 1881972, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2420418).

1881972 is an abundant number, since it is smaller than the sum of its proper divisors (2958864).

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

1881972 is a wasteful number, since it uses less digits than its factorization.

1881972 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 928 (or 923 counting only the distinct ones).

The product of its digits is 8064, while the sum is 36.

The square root of 1881972 is about 1371.8498460109. The cubic root of 1881972 is about 123.4632540505.

Subtracting 1881972 from its reverse (2791881), we obtain a palindrome (909909).

The spelling of 1881972 in words is "one million, eight hundred eighty-one thousand, nine hundred seventy-two".