1012870721 has 4 divisors (see below), whose sum is σ = 1016527572. Its totient is φ = 1009213872.

The previous prime is 1012870717. The next prime is 1012870739. The reversal of 1012870721 is 1270782101.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 232227121 + 780643600 = 15239^2 + 27940^2 .

It is a cyclic number.

It is not a de Polignac number, because 1012870721 - 2² = 1012870717 is a prime.

It is a super-3 number, since 3×1012870721³ (a number of 28 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1012870741) 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, 1828010 + ... + 1828563.

It is an arithmetic number, because the mean of its divisors is an integer number (254131893).

Almost surely, 2^1012870721 is an apocalyptic number.

It is an amenable number.

1012870721 is a deficient number, since it is larger than the sum of its proper divisors (3656851).

1012870721 is an equidigital number, since it uses as much as digits as its factorization.

1012870721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3656850.

The product of its (nonzero) digits is 1568, while the sum is 29.

The square root of 1012870721 is about 31825.6299387773. The cubic root of 1012870721 is about 1004.2719646639.

The spelling of 1012870721 in words is "one billion, twelve million, eight hundred seventy thousand, seven hundred twenty-one".