1630736881 has 4 divisors (see below), whose sum is σ = 1651379200. Its totient is φ = 1610094564.

The previous prime is 1630736879. The next prime is 1630736953. The reversal of 1630736881 is 1886370361.

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: 1886370361 = 59 ⋅31972379.

It is a cyclic number.

It is not a de Polignac number, because 1630736881 - 2¹ = 1630736879 is a prime.

It is a super-2 number, since 2×1630736881² = 5318605550107216322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1630736801) 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, 10321041 + ... + 10321198.

It is an arithmetic number, because the mean of its divisors is an integer number (412844800).

Almost surely, 2^1630736881 is an apocalyptic number.

It is an amenable number.

1630736881 is a deficient number, since it is larger than the sum of its proper divisors (20642319).

1630736881 is an equidigital number, since it uses as much as digits as its factorization.

1630736881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20642318.

The product of its (nonzero) digits is 145152, while the sum is 43.

The square root of 1630736881 is about 40382.3833001471. The cubic root of 1630736881 is about 1177.0492396725.

The spelling of 1630736881 in words is "one billion, six hundred thirty million, seven hundred thirty-six thousand, eight hundred eighty-one".