1972139993 has 2 divisors, whose sum is σ = 1972139994. Its totient is φ = 1972139992.

The previous prime is 1972139987. The next prime is 1972139999. The reversal of 1972139993 is 3999312791.

It is a happy number.

It is a balanced prime because it is at equal distance from previous prime (1972139987) and next prime (1972139999).

It can be written as a sum of positive squares in only one way, i.e., 1956115984 + 16024009 = 44228^2 + 4003^2 .

It is an emirp because it is prime and its reverse (3999312791) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1972139993 - 2¹⁰ = 1972138969 is a prime.

It is not a weakly prime, because it can be changed into another prime (1972139999) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 986069996 + 986069997.

It is an arithmetic number, because the mean of its divisors is an integer number (986069997).

Almost surely, 2^1972139993 is an apocalyptic number.

It is an amenable number.

1972139993 is a deficient number, since it is larger than the sum of its proper divisors (1).

1972139993 is an equidigital number, since it uses as much as digits as its factorization.

1972139993 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 826686, while the sum is 53.

The square root of 1972139993 is about 44408.7828362814. The cubic root of 1972139993 is about 1254.0434382229.

The spelling of 1972139993 in words is "one billion, nine hundred seventy-two million, one hundred thirty-nine thousand, nine hundred ninety-three".