1011621881 has 2 divisors, whose sum is σ = 1011621882. Its totient is φ = 1011621880.

The previous prime is 1011621869. The next prime is 1011621893. The reversal of 1011621881 is 1881261101.

It is a balanced prime because it is at equal distance from previous prime (1011621869) and next prime (1011621893).

It can be written as a sum of positive squares in only one way, i.e., 558613225 + 453008656 = 23635^2 + 21284^2 .

It is an emirp because it is prime and its reverse (1881261101) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1011621881 is a prime.

It is a super-2 number, since 2×1011621881² = 2046757660235956322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1011641881) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 505810940 + 505810941.

It is an arithmetic number, because the mean of its divisors is an integer number (505810941).

Almost surely, 2^1011621881 is an apocalyptic number.

It is an amenable number.

1011621881 is a deficient number, since it is larger than the sum of its proper divisors (1).

1011621881 is an equidigital number, since it uses as much as digits as its factorization.

1011621881 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 768, while the sum is 29.

The square root of 1011621881 is about 31806.0038514743. The cubic root of 1011621881 is about 1003.8590489181.

Adding to 1011621881 its reverse (1881261101), we get a palindrome (2892882982).

The spelling of 1011621881 in words is "one billion, eleven million, six hundred twenty-one thousand, eight hundred eighty-one".