1861144431 has 16 divisors (see below), whose sum is σ = 2495035488. Its totient is φ = 1234022400.

The previous prime is 1861144409. The next prime is 1861144433. The reversal of 1861144431 is 1344411681.

It is not a de Polignac number, because 1861144431 - 2¹⁰ = 1861143407 is a prime.

It is a super-2 number, since 2×1861144431² = 6927717186084627522, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1861144392 and 1861144401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1861144433) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 893311 + ... + 895391.

It is an arithmetic number, because the mean of its divisors is an integer number (155939718).

Almost surely, 2^1861144431 is an apocalyptic number.

1861144431 is a deficient number, since it is larger than the sum of its proper divisors (633891057).

1861144431 is a wasteful number, since it uses less digits than its factorization.

1861144431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3562.

The product of its digits is 9216, while the sum is 33.

The square root of 1861144431 is about 43140.9831946376. The cubic root of 1861144431 is about 1230.0611226153.

The spelling of 1861144431 in words is "one billion, eight hundred sixty-one million, one hundred forty-four thousand, four hundred thirty-one".