81215030 has 16 divisors (see below), whose sum is σ = 157432464. Its totient is φ = 29987040.

The previous prime is 81215011. The next prime is 81215041. The reversal of 81215030 is 3051218.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 81214993 and 81215011.

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, 312236 + ... + 312495.

It is an arithmetic number, because the mean of its divisors is an integer number (9839529).

Almost surely, 2^81215030 is an apocalyptic number.

81215030 is a deficient number, since it is larger than the sum of its proper divisors (76217434).

81215030 is a wasteful number, since it uses less digits than its factorization.

81215030 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 624751.

The product of its (nonzero) digits is 240, while the sum is 20.

The square root of 81215030 is about 9011.9381933078. The cubic root of 81215030 is about 433.0574055351.

Adding to 81215030 its reverse (3051218), we get a palindrome (84266248).

The spelling of 81215030 in words is "eighty-one million, two hundred fifteen thousand, thirty".