2021878451 has 2 divisors, whose sum is σ = 2021878452. Its totient is φ = 2021878450.

The previous prime is 2021878409. The next prime is 2021878583. The reversal of 2021878451 is 1548781202.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2021878451 is a prime.

It is not a weakly prime, because it can be changed into another prime (2021878351) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1010939225 + 1010939226.

It is an arithmetic number, because the mean of its divisors is an integer number (1010939226).

Almost surely, 2^2021878451 is an apocalyptic number.

2021878451 is a deficient number, since it is larger than the sum of its proper divisors (1).

2021878451 is an equidigital number, since it uses as much as digits as its factorization.

2021878451 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 35840, while the sum is 38.

The square root of 2021878451 is about 44965.3027455615. The cubic root of 2021878451 is about 1264.4985855115.

The spelling of 2021878451 in words is "two billion, twenty-one million, eight hundred seventy-eight thousand, four hundred fifty-one".