81052780 has 24 divisors (see below), whose sum is σ = 170597952. Its totient is φ = 32347392.

The previous prime is 81052771. The next prime is 81052789. The reversal of 81052780 is 8725018.

It is an interprime number because it is at equal distance from previous prime (81052771) and next prime (81052789).

It is not an unprimeable number, because it can be changed into a prime (81052789) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4884 + ... + 13636.

It is an arithmetic number, because the mean of its divisors is an integer number (7108248).

Almost surely, 2^81052780 is an apocalyptic number.

It is an amenable number.

81052780 is an abundant number, since it is smaller than the sum of its proper divisors (89545172).

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

81052780 is a wasteful number, since it uses less digits than its factorization.

81052780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9225 (or 9223 counting only the distinct ones).

The product of its (nonzero) digits is 4480, while the sum is 31.

The square root of 81052780 is about 9002.9317447152. The cubic root of 81052780 is about 432.7688283817.

Adding to 81052780 its reverse (8725018), we get a palindrome (89777798).

The spelling of 81052780 in words is "eighty-one million, fifty-two thousand, seven hundred eighty".