1630843861 has 4 divisors (see below), whose sum is σ = 1630936000. Its totient is φ = 1630751724.

The previous prime is 1630843859. The next prime is 1630843873. The reversal of 1630843861 is 1683480361.

It is a happy number.

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 a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 1630843861 - 2¹ = 1630843859 is a prime.

It is a super-2 number, since 2×1630843861² = 5319303397922774642, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1630843661) 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, 10221 + ... + 58018.

It is an arithmetic number, because the mean of its divisors is an integer number (407734000).

Almost surely, 2^1630843861 is an apocalyptic number.

It is an amenable number.

1630843861 is a deficient number, since it is larger than the sum of its proper divisors (92139).

1630843861 is an equidigital number, since it uses as much as digits as its factorization.

1630843861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 92138.

The product of its (nonzero) digits is 82944, while the sum is 40.

The square root of 1630843861 is about 40383.7078659204. The cubic root of 1630843861 is about 1177.0749781338.

The spelling of 1630843861 in words is "one billion, six hundred thirty million, eight hundred forty-three thousand, eight hundred sixty-one".