1694978961 has 16 divisors (see below), whose sum is σ = 2561912640. Its totient is φ = 988165440.

The previous prime is 1694978959. The next prime is 1694978969. The reversal of 1694978961 is 1698794961.

It is a happy number.

It is not a de Polignac number, because 1694978961 - 2¹ = 1694978959 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1694978895 and 1694978904.

It is not an unprimeable number, because it can be changed into a prime (1694978969) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1142970 + ... + 1144451.

It is an arithmetic number, because the mean of its divisors is an integer number (160119540).

Almost surely, 2^1694978961 is an apocalyptic number.

It is an amenable number.

1694978961 is a deficient number, since it is larger than the sum of its proper divisors (866933679).

1694978961 is a wasteful number, since it uses less digits than its factorization.

1694978961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2287456.

The product of its digits is 5878656, while the sum is 60.

The square root of 1694978961 is about 41170.1221883054. The cubic root of 1694978961 is about 1192.3070281826.

The spelling of 1694978961 in words is "one billion, six hundred ninety-four million, nine hundred seventy-eight thousand, nine hundred sixty-one".