1972919869 has 2 divisors, whose sum is σ = 1972919870. Its totient is φ = 1972919868.

The previous prime is 1972919863. The next prime is 1972919911. The reversal of 1972919869 is 9689192791.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1718102500 + 254817369 = 41450^2 + 15963^2 .

It is an emirp because it is prime and its reverse (9689192791) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1972919869 - 2⁹ = 1972919357 is a prime.

It is a super-2 number, since 2×1972919869² = 7784825618989954322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1972919863) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 986459934 + 986459935.

It is an arithmetic number, because the mean of its divisors is an integer number (986459935).

Almost surely, 2^1972919869 is an apocalyptic number.

It is an amenable number.

1972919869 is a deficient number, since it is larger than the sum of its proper divisors (1).

1972919869 is an equidigital number, since it uses as much as digits as its factorization.

1972919869 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4408992, while the sum is 61.

The square root of 1972919869 is about 44417.5626188561. The cubic root of 1972919869 is about 1254.2087188312.

The spelling of 1972919869 in words is "one billion, nine hundred seventy-two million, nine hundred nineteen thousand, eight hundred sixty-nine".