81030556 has 12 divisors (see below), whose sum is σ = 142112992. Its totient is φ = 40426848.

The previous prime is 81030503. The next prime is 81030557. The reversal of 81030556 is 65503018.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81030557) 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, 20025 + ... + 23728.

Almost surely, 2^81030556 is an apocalyptic number.

It is an amenable number.

81030556 is a deficient number, since it is larger than the sum of its proper divisors (61082436).

81030556 is a wasteful number, since it uses less digits than its factorization.

81030556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44220 (or 44218 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 28.

The square root of 81030556 is about 9001.6973954916. The cubic root of 81030556 is about 432.7292708916.

The spelling of 81030556 in words is "eighty-one million, thirty thousand, five hundred fifty-six".