2131436691 has 6 divisors (see below), whose sum is σ = 3078741900. Its totient is φ = 1420957788.

The previous prime is 2131436677. The next prime is 2131436717. The reversal of 2131436691 is 1966341312.

2131436691 is a `hidden beast` number, since 2 + 131 + 436 + 6 + 91 = 666.

It is not a de Polignac number, because 2131436691 - 2⁶ = 2131436627 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2131436621) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 118413141 + ... + 118413158.

It is an arithmetic number, because the mean of its divisors is an integer number (513123650).

Almost surely, 2^2131436691 is an apocalyptic number.

2131436691 is a deficient number, since it is larger than the sum of its proper divisors (947305209).

2131436691 is a wasteful number, since it uses less digits than its factorization.

2131436691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 236826305 (or 236826302 counting only the distinct ones).

The product of its digits is 23328, while the sum is 36.

The square root of 2131436691 is about 46167.4852141634. The cubic root of 2131436691 is about 1286.9375688532.

The spelling of 2131436691 in words is "two billion, one hundred thirty-one million, four hundred thirty-six thousand, six hundred ninety-one".