99951421 has 2 divisors, whose sum is σ = 99951422. Its totient is φ = 99951420.

The previous prime is 99951407. The next prime is 99951427. The reversal of 99951421 is 12415999.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 99800100 + 151321 = 9990^2 + 389^2 .

It is an emirp because it is prime and its reverse (12415999) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 99951421 - 2⁵ = 99951389 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (99951427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49975710 + 49975711.

It is an arithmetic number, because the mean of its divisors is an integer number (49975711).

Almost surely, 2^99951421 is an apocalyptic number.

It is an amenable number.

99951421 is a deficient number, since it is larger than the sum of its proper divisors (1).

99951421 is an equidigital number, since it uses as much as digits as its factorization.

99951421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 29160, while the sum is 40.

The square root of 99951421 is about 9997.5707549384. The cubic root of 99951421 is about 464.0837099391.

The spelling of 99951421 in words is "ninety-nine million, nine hundred fifty-one thousand, four hundred twenty-one".