1985100981 has 8 divisors (see below), whose sum is σ = 2786106720. Its totient is φ = 1253747952.

The previous prime is 1985100973. The next prime is 1985100983. The reversal of 1985100981 is 1890015891.

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

It is not a de Polignac number, because 1985100981 - 2³ = 1985100973 is a prime.

It is a super-2 number, since 2×1985100981² = 7881251809534324722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1985100983) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17413110 + ... + 17413223.

It is an arithmetic number, because the mean of its divisors is an integer number (348263340).

Almost surely, 2^1985100981 is an apocalyptic number.

It is an amenable number.

1985100981 is a deficient number, since it is larger than the sum of its proper divisors (801005739).

1985100981 is a wasteful number, since it uses less digits than its factorization.

1985100981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34826355.

The product of its (nonzero) digits is 25920, while the sum is 42.

The square root of 1985100981 is about 44554.4720651025. The cubic root of 1985100981 is about 1256.7846507986.

The spelling of 1985100981 in words is "one billion, nine hundred eighty-five million, one hundred thousand, nine hundred eighty-one".