894747619921 has 9 divisors (see below), whose sum is σ = 917142756699. Its totient is φ = 872886670800.

The previous prime is 894747619907. The next prime is 894747619933. The reversal of 894747619921 is 129916747498.

The square root of 894747619921 is 945911.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 43113954321 + 851633665600 = 207639^2 + 922840^2 .

It is not a de Polignac number, because 894747619921 - 2¹⁷ = 894747488849 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (894747616921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 38770816 + ... + 38793886.

Almost surely, 2^894747619921 is an apocalyptic number.

894747619921 is the 945911-st square number.

894747619921 is the 472956-th centered octagonal number.

It is an amenable number.

894747619921 is a deficient number, since it is larger than the sum of its proper divisors (22395136778).

894747619921 is an frugal number, since it uses more digits than its factorization.

894747619921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46224 (or 23112 counting only the distinct ones).

The product of its digits is 54867456, while the sum is 67.

The spelling of 894747619921 in words is "eight hundred ninety-four billion, seven hundred forty-seven million, six hundred nineteen thousand, nine hundred twenty-one".