81470766 has 32 divisors (see below), whose sum is σ = 185800608. Its totient is φ = 23592960.

The previous prime is 81470747. The next prime is 81470771. The reversal of 81470766 is 66707418.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 29395 + ... + 32046.

It is an arithmetic number, because the mean of its divisors is an integer number (5806269).

Almost surely, 2^81470766 is an apocalyptic number.

81470766 is an abundant number, since it is smaller than the sum of its proper divisors (104329842).

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

81470766 is a wasteful number, since it uses less digits than its factorization.

81470766 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61476.

The product of its (nonzero) digits is 56448, while the sum is 39.

The square root of 81470766 is about 9026.1157759027. The cubic root of 81470766 is about 433.5114771822.

The spelling of 81470766 in words is "eighty-one million, four hundred seventy thousand, seven hundred sixty-six".