81630290938 has 64 divisors (see below), whose sum is σ = 149537894400. Its totient is φ = 32642326080.

The previous prime is 81630290873. The next prime is 81630290939. The reversal of 81630290938 is 83909203618.

It is a junction number, because it is equal to n+sod(n) for n = 81630290891 and 81630290900.

It is not an unprimeable number, because it can be changed into a prime (81630290939) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 8842281 + ... + 8851507.

It is an arithmetic number, because the mean of its divisors is an integer number (2336529600).

Almost surely, 2^81630290938 is an apocalyptic number.

81630290938 is a deficient number, since it is larger than the sum of its proper divisors (67907603462).

81630290938 is a wasteful number, since it uses less digits than its factorization.

81630290938 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9755.

The product of its (nonzero) digits is 559872, while the sum is 49.

The spelling of 81630290938 in words is "eighty-one billion, six hundred thirty million, two hundred ninety thousand, nine hundred thirty-eight".