1021000019 has 4 divisors (see below), whose sum is σ = 1099538496. Its totient is φ = 942461544.

The previous prime is 1021000009. The next prime is 1021000027. The reversal of 1021000019 is 9100001201.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9100001201 = 71 ⋅128169031.

It is a cyclic number.

It is not a de Polignac number, because 1021000019 - 2¹² = 1020995923 is a prime.

It is a super-2 number, since 2×1021000019² = 2084882077596000722, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1020999967 and 1021000012.

It is not an unprimeable number, because it can be changed into a prime (1021000009) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 39269219 + ... + 39269244.

It is an arithmetic number, because the mean of its divisors is an integer number (274884624).

Almost surely, 2^1021000019 is an apocalyptic number.

1021000019 is a deficient number, since it is larger than the sum of its proper divisors (78538477).

1021000019 is an equidigital number, since it uses as much as digits as its factorization.

1021000019 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78538476.

The product of its (nonzero) digits is 18, while the sum is 14.

The square root of 1021000019 is about 31953.0909146517. The cubic root of 1021000019 is about 1006.9515700308.

The spelling of 1021000019 in words is "one billion, twenty-one million, nineteen", and thus it is an aban number and an uban number.