812150721 has 12 divisors (see below), whose sum is σ = 1186288740. Its totient is φ = 535349760.

The previous prime is 812150693. The next prime is 812150737. The reversal of 812150721 is 127051218.

It can be written as a sum of positive squares in 2 ways, for example, as 293951025 + 518199696 = 17145^2 + 22764^2 .

It is not a de Polignac number, because 812150721 - 2⁶ = 812150657 is a prime.

It is not an unprimeable number, because it can be changed into a prime (812150221) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 506160 + ... + 507761.

It is an arithmetic number, because the mean of its divisors is an integer number (98857395).

Almost surely, 2^812150721 is an apocalyptic number.

It is an amenable number.

812150721 is a deficient number, since it is larger than the sum of its proper divisors (374138019).

812150721 is a wasteful number, since it uses less digits than its factorization.

812150721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1014016 (or 1014013 counting only the distinct ones).

The product of its (nonzero) digits is 1120, while the sum is 27.

The square root of 812150721 is about 28498.2582099328. The cubic root of 812150721 is about 932.9940584741.

The spelling of 812150721 in words is "eight hundred twelve million, one hundred fifty thousand, seven hundred twenty-one".