81778030 has 16 divisors (see below), whose sum is σ = 147578400. Its totient is φ = 32627232.

The previous prime is 81778001. The next prime is 81778043. The reversal of 81778030 is 3087718.

It is a happy number.

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, 6330 + ... + 14269.

It is an arithmetic number, because the mean of its divisors is an integer number (9223650).

Almost surely, 2^81778030 is an apocalyptic number.

81778030 is a deficient number, since it is larger than the sum of its proper divisors (65800370).

81778030 is a wasteful number, since it uses less digits than its factorization.

81778030 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21003.

The product of its (nonzero) digits is 9408, while the sum is 34.

The square root of 81778030 is about 9043.1205897080. The cubic root of 81778030 is about 434.0557843448.

The spelling of 81778030 in words is "eighty-one million, seven hundred seventy-eight thousand, thirty".