351949921 has 2 divisors, whose sum is σ = 351949922. Its totient is φ = 351949920.

The previous prime is 351949909. The next prime is 351949943. The reversal of 351949921 is 129949153.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 351937600 + 12321 = 18760^2 + 111^2 .

It is an emirp because it is prime and its reverse (129949153) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-351949921 is a prime.

It is not a weakly prime, because it can be changed into another prime (351949951) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 175974960 + 175974961.

It is an arithmetic number, because the mean of its divisors is an integer number (175974961).

Almost surely, 2^351949921 is an apocalyptic number.

It is an amenable number.

351949921 is a deficient number, since it is larger than the sum of its proper divisors (1).

351949921 is an equidigital number, since it uses as much as digits as its factorization.

351949921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 87480, while the sum is 43.

The square root of 351949921 is about 18760.3283819873. The cubic root of 351949921 is about 706.0361813267.

The spelling of 351949921 in words is "three hundred fifty-one million, nine hundred forty-nine thousand, nine hundred twenty-one".