1025155421 has 2 divisors, whose sum is σ = 1025155422. Its totient is φ = 1025155420.

The previous prime is 1025155363. The next prime is 1025155427. The reversal of 1025155421 is 1245515201.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1024320025 + 835396 = 32005^2 + 914^2 .

It is a cyclic number.

It is not a de Polignac number, because 1025155421 - 2⁶ = 1025155357 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1025155427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 512577710 + 512577711.

It is an arithmetic number, because the mean of its divisors is an integer number (512577711).

Almost surely, 2^1025155421 is an apocalyptic number.

It is an amenable number.

1025155421 is a deficient number, since it is larger than the sum of its proper divisors (1).

1025155421 is an equidigital number, since it uses as much as digits as its factorization.

1025155421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2000, while the sum is 26.

The square root of 1025155421 is about 32018.0483633840. The cubic root of 1025155421 is about 1008.3157961813.

The spelling of 1025155421 in words is "one billion, twenty-five million, one hundred fifty-five thousand, four hundred twenty-one".