1321020019 has 16 divisors (see below), whose sum is σ = 1552287744. Its totient is φ = 1111651200.

The previous prime is 1321020017. The next prime is 1321020053. The reversal of 1321020019 is 9100201231.

It is not a de Polignac number, because 1321020019 - 2¹ = 1321020017 is a prime.

It is a super-2 number, since 2×1321020019² = 3490187781197520722, 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 = 1321019978 and 1321020005.

It is not an unprimeable number, because it can be changed into a prime (1321020013) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 76374 + ... + 92059.

It is an arithmetic number, because the mean of its divisors is an integer number (97017984).

Almost surely, 2^1321020019 is an apocalyptic number.

1321020019 is a deficient number, since it is larger than the sum of its proper divisors (231267725).

1321020019 is a wasteful number, since it uses less digits than its factorization.

1321020019 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 168498.

The product of its (nonzero) digits is 108, while the sum is 19.

The square root of 1321020019 is about 36345.8390878516. The cubic root of 1321020019 is about 1097.2437936406.

The spelling of 1321020019 in words is "one billion, three hundred twenty-one million, twenty thousand, nineteen".