1971953913 has 16 divisors (see below), whose sum is σ = 2799328896. Its totient is φ = 1230462720.

The previous prime is 1971953903. The next prime is 1971953939. The reversal of 1971953913 is 3193591791.

It is a happy number.

It is not a de Polignac number, because 1971953913 - 2⁴ = 1971953897 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1971953903) 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, 97581 + ... + 116042.

It is an arithmetic number, because the mean of its divisors is an integer number (174958056).

Almost surely, 2^1971953913 is an apocalyptic number.

It is an amenable number.

1971953913 is a deficient number, since it is larger than the sum of its proper divisors (827374983).

1971953913 is a wasteful number, since it uses less digits than its factorization.

1971953913 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 213824.

The product of its digits is 229635, while the sum is 48.

The square root of 1971953913 is about 44406.6877057949. The cubic root of 1971953913 is about 1254.0039954951.

The spelling of 1971953913 in words is "one billion, nine hundred seventy-one million, nine hundred fifty-three thousand, nine hundred thirteen".