81520276 has 24 divisors (see below), whose sum is σ = 149375520. Its totient is φ = 38875872.

The previous prime is 81520267. The next prime is 81520301. The reversal of 81520276 is 67202518.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5395 + ... + 13861.

It is an arithmetic number, because the mean of its divisors is an integer number (6223980).

Almost surely, 2^81520276 is an apocalyptic number.

It is an amenable number.

81520276 is a deficient number, since it is larger than the sum of its proper divisors (67855244).

81520276 is a wasteful number, since it uses less digits than its factorization.

81520276 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8583 (or 8581 counting only the distinct ones).

The product of its (nonzero) digits is 6720, while the sum is 31.

The square root of 81520276 is about 9028.8579565746. The cubic root of 81520276 is about 433.5992747568.

It can be divided in two parts, 81520 and 276, that added together give a square (81796 = 286²).

The spelling of 81520276 in words is "eighty-one million, five hundred twenty thousand, two hundred seventy-six".