1021878461 has 2 divisors, whose sum is σ = 1021878462. Its totient is φ = 1021878460.

The previous prime is 1021878437. The next prime is 1021878467. The reversal of 1021878461 is 1648781201.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 839898361 + 181980100 = 28981^2 + 13490^2 .

It is a cyclic number.

It is not a de Polignac number, because 1021878461 - 2²⁶ = 954769597 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1021878467) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 510939230 + 510939231.

It is an arithmetic number, because the mean of its divisors is an integer number (510939231).

Almost surely, 2^1021878461 is an apocalyptic number.

It is an amenable number.

1021878461 is a deficient number, since it is larger than the sum of its proper divisors (1).

1021878461 is an equidigital number, since it uses as much as digits as its factorization.

1021878461 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 21504, while the sum is 38.

The square root of 1021878461 is about 31966.8337656390. The cubic root of 1021878461 is about 1007.2402722753.

The spelling of 1021878461 in words is "one billion, twenty-one million, eight hundred seventy-eight thousand, four hundred sixty-one".