1981229 has 8 divisors (see below), whose sum is σ = 2031480. Its totient is φ = 1931776.

The previous prime is 1981201. The next prime is 1981237. The reversal of 1981229 is 9221891.

It is a happy number.

1981229 is nontrivially palindromic in base 4.

It can be written as a sum of positive squares in 4 ways, for example, as 96100 + 1885129 = 310^2 + 1373^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1981229 is a prime.

It is a super-3 number, since 3×1981229³ = 23330566466027615967, which contains 333 as substring.

It is a Duffinian number.

It is a plaindrome in base 11.

It is a junction number, because it is equal to n+sod(n) for n = 1981195 and 1981204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1981429) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 9959 + ... + 10155.

It is an arithmetic number, because the mean of its divisors is an integer number (253935).

2^1981229 is an apocalyptic number.

It is an amenable number.

1981229 is a deficient number, since it is larger than the sum of its proper divisors (50251).

1981229 is a wasteful number, since it uses less digits than its factorization.

1981229 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 399.

The product of its digits is 2592, while the sum is 32.

The square root of 1981229 is about 1407.5613663354. The cubic root of 1981229 is about 125.5966990694.

It can be divided in two parts, 198 and 1229, that multiplied together give a palindrome (243342).

The spelling of 1981229 in words is "one million, nine hundred eighty-one thousand, two hundred twenty-nine".