10399421 has 4 divisors (see below), whose sum is σ = 10641312. Its totient is φ = 10157532.

The previous prime is 10399409. The next prime is 10399423. The reversal of 10399421 is 12499301.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 10399421 - 2⁶ = 10399357 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10399423) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 120881 + ... + 120966.

It is an arithmetic number, because the mean of its divisors is an integer number (2660328).

Almost surely, 2^10399421 is an apocalyptic number.

It is an amenable number.

10399421 is a deficient number, since it is larger than the sum of its proper divisors (241891).

10399421 is an equidigital number, since it uses as much as digits as its factorization.

10399421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 241890.

The product of its (nonzero) digits is 1944, while the sum is 29.

The square root of 10399421 is about 3224.8133279308. The cubic root of 10399421 is about 218.2745257904.

The spelling of 10399421 in words is "ten million, three hundred ninety-nine thousand, four hundred twenty-one".