1861047980 has 48 divisors (see below), whose sum is σ = 4266966816. Its totient is φ = 676193280.

The previous prime is 1861047959. The next prime is 1861047983. The reversal of 1861047980 is 897401681.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is not an unprimeable number, because it can be changed into a prime (1861047983) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 348692 + ... + 353988.

It is an arithmetic number, because the mean of its divisors is an integer number (88895142).

Almost surely, 2^1861047980 is an apocalyptic number.

1861047980 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1861047980 is an abundant number, since it is smaller than the sum of its proper divisors (2405918836).

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

1861047980 is a wasteful number, since it uses less digits than its factorization.

1861047980 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6914 (or 6912 counting only the distinct ones).

The product of its (nonzero) digits is 96768, while the sum is 44.

The square root of 1861047980 is about 43139.8653219965. The cubic root of 1861047980 is about 1230.0398735614.

The spelling of 1861047980 in words is "one billion, eight hundred sixty-one million, forty-seven thousand, nine hundred eighty".