81652880 has 40 divisors (see below), whose sum is σ = 199838400. Its totient is φ = 30941568.

The previous prime is 81652871. The next prime is 81652889. The reversal of 81652880 is 8825618.

It is an interprime number because it is at equal distance from previous prime (81652871) and next prime (81652889).

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (38).

It is not an unprimeable number, because it can be changed into a prime (81652889) 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, 25340 + ... + 28379.

It is an arithmetic number, because the mean of its divisors is an integer number (4995960).

Almost surely, 2^81652880 is an apocalyptic number.

81652880 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

81652880 is an abundant number, since it is smaller than the sum of its proper divisors (118185520).

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

81652880 is a wasteful number, since it uses less digits than its factorization.

81652880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53751 (or 53745 counting only the distinct ones).

The product of its (nonzero) digits is 30720, while the sum is 38.

The square root of 81652880 is about 9036.1983156635. The cubic root of 81652880 is about 433.8342504527.

The spelling of 81652880 in words is "eighty-one million, six hundred fifty-two thousand, eight hundred eighty".