1021870081 has 4 divisors (see below), whose sum is σ = 1054833664. Its totient is φ = 988906500.

The previous prime is 1021870079. The next prime is 1021870093. The reversal of 1021870081 is 1800781201.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1800781201 = 10789 ⋅166909.

It is a cyclic number.

It is not a de Polignac number, because 1021870081 - 2¹ = 1021870079 is a prime.

It is a super-2 number, since 2×1021870081² = 2088436924885893122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1021870061) 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, 16481745 + ... + 16481806.

It is an arithmetic number, because the mean of its divisors is an integer number (263708416).

It is a Proth number, since it is equal to 31185 ⋅ 2¹⁵ + 1 and 31185 < 2¹⁵.

Almost surely, 2^1021870081 is an apocalyptic number.

It is an amenable number.

1021870081 is a deficient number, since it is larger than the sum of its proper divisors (32963583).

1021870081 is an equidigital number, since it uses as much as digits as its factorization.

1021870081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32963582.

The product of its (nonzero) digits is 896, while the sum is 28.

The square root of 1021870081 is about 31966.7026920200. The cubic root of 1021870081 is about 1007.2375189483.

The spelling of 1021870081 in words is "one billion, twenty-one million, eight hundred seventy thousand, eighty-one".