994251681 has 48 divisors (see below), whose sum is σ = 1565600400. Its totient is φ = 605552640.

The previous prime is 994251611. The next prime is 994251691. The reversal of 994251681 is 186152499.

994251681 is a `hidden beast` number, since 99 + 42 + 516 + 8 + 1 = 666.

It can be written as a sum of positive squares in 8 ways, for example, as 15563025 + 978688656 = 3945^2 + 31284^2 .

It is not a de Polignac number, because 994251681 - 2¹³ = 994243489 is a prime.

It is a super-2 number, since 2×994251681² = 1977072810342651522, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (994251611) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2214145 + ... + 2214593.

It is an arithmetic number, because the mean of its divisors is an integer number (32616675).

Almost surely, 2^994251681 is an apocalyptic number.

It is an amenable number.

994251681 is a deficient number, since it is larger than the sum of its proper divisors (571348719).

994251681 is a wasteful number, since it uses less digits than its factorization.

994251681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 866 (or 863 counting only the distinct ones).

The product of its digits is 155520, while the sum is 45.

The square root of 994251681 is about 31531.7567065332. The cubic root of 994251681 is about 998.0802104332.

The spelling of 994251681 in words is "nine hundred ninety-four million, two hundred fifty-one thousand, six hundred eighty-one".