100020945 has 16 divisors (see below), whose sum is σ = 169447680. Its totient is φ = 50206464.

The previous prime is 100020929. The next prime is 100021003. The reversal of 100020945 is 549020001.

It is not a de Polignac number, because 100020945 - 2⁴ = 100020929 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 195865 + ... + 196374.

It is an arithmetic number, because the mean of its divisors is an integer number (10590480).

Almost surely, 2^100020945 is an apocalyptic number.

100020945 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

100020945 is a deficient number, since it is larger than the sum of its proper divisors (69426735).

100020945 is a wasteful number, since it uses less digits than its factorization.

100020945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 392264.

The product of its (nonzero) digits is 360, while the sum is 21.

The square root of 100020945 is about 10001.0471951691. The cubic root of 100020945 is about 464.1912871251.

Adding to 100020945 its reverse (549020001), we get a palindrome (649040946).

It can be divided in two parts, 1000 and 20945, that added together give a triangular number (21945 = T₂₀₉).

The spelling of 100020945 in words is "one hundred million, twenty thousand, nine hundred forty-five".