1291021351 has 2 divisors, whose sum is σ = 1291021352. Its totient is φ = 1291021350.

The previous prime is 1291021343. The next prime is 1291021409. The reversal of 1291021351 is 1531201921.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1291021351 - 2³ = 1291021343 is a prime.

It is a super-2 number, since 2×1291021351² = 3333472257475730402, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1291021951) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 645510675 + 645510676.

It is an arithmetic number, because the mean of its divisors is an integer number (645510676).

Almost surely, 2^1291021351 is an apocalyptic number.

1291021351 is a deficient number, since it is larger than the sum of its proper divisors (1).

1291021351 is an equidigital number, since it uses as much as digits as its factorization.

1291021351 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 540, while the sum is 25.

The square root of 1291021351 is about 35930.7855605747. The cubic root of 1291021351 is about 1088.8744521506.

The spelling of 1291021351 in words is "one billion, two hundred ninety-one million, twenty-one thousand, three hundred fifty-one".