81051000 has 64 divisors (see below), whose sum is σ = 252888480. Its totient is φ = 21612800.

The previous prime is 81050993. The next prime is 81051007. The reversal of 81051000 is 15018.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (81050993) and next prime (81051007).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81051007) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10509 + ... + 16508.

Almost surely, 2^81051000 is an apocalyptic number.

It is an amenable number.

81051000 is an abundant number, since it is smaller than the sum of its proper divisors (171837480).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81051000 is a wasteful number, since it uses less digits than its factorization.

81051000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27041 (or 27027 counting only the distinct ones).

The product of its (nonzero) digits is 40, while the sum is 15.

The square root of 81051000 is about 9002.8328874860. The cubic root of 81051000 is about 432.7656603466.

Adding to 81051000 its reverse (15018), we get a palindrome (81066018).

The spelling of 81051000 in words is "eighty-one million, fifty-one thousand".