1981762553 has 2 divisors, whose sum is σ = 1981762554. Its totient is φ = 1981762552.

The previous prime is 1981762499. The next prime is 1981762577. The reversal of 1981762553 is 3552671891.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1154164729 + 827597824 = 33973^2 + 28768^2 .

It is a cyclic number.

It is not a de Polignac number, because 1981762553 - 2⁸ = 1981762297 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1981762498 and 1981762507.

It is not a weakly prime, because it can be changed into another prime (1981762753) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 990881276 + 990881277.

It is an arithmetic number, because the mean of its divisors is an integer number (990881277).

Almost surely, 2^1981762553 is an apocalyptic number.

It is an amenable number.

1981762553 is a deficient number, since it is larger than the sum of its proper divisors (1).

1981762553 is an equidigital number, since it uses as much as digits as its factorization.

1981762553 is an evil number, because the sum of its binary digits is even.

The product of its digits is 453600, while the sum is 47.

The square root of 1981762553 is about 44516.9917334943. The cubic root of 1981762553 is about 1256.0797262417.

The spelling of 1981762553 in words is "one billion, nine hundred eighty-one million, seven hundred sixty-two thousand, five hundred fifty-three".