1021012100209 has 8 divisors (see below), whose sum is σ = 1023996708072. Its totient is φ = 1018028014080.

The previous prime is 1021012100203. The next prime is 1021012100233. The reversal of 1021012100209 is 9020012101201.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 3643329600 + 1017368770609 = 60360^2 + 1008647^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 1021012100209 - 2³ = 1021012100201 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1021012100201) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3977767 + ... + 4226659.

It is an arithmetic number, because the mean of its divisors is an integer number (127999588509).

Almost surely, 2^{1021012100209} is an apocalyptic number.

It is an amenable number.

1021012100209 is a deficient number, since it is larger than the sum of its proper divisors (2984607863).

1021012100209 is a wasteful number, since it uses less digits than its factorization.

1021012100209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 260867.

The product of its (nonzero) digits is 72, while the sum is 19.

The spelling of 1021012100209 in words is "one trillion, twenty-one billion, twelve million, one hundred thousand, two hundred nine".