15699401 has 4 divisors (see below), whose sum is σ = 15707904. Its totient is φ = 15690900.

The previous prime is 15699391. The next prime is 15699403. The reversal of 15699401 is 10499651.

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, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 10499651 = 331 ⋅31721.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-15699401 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (15699403) 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, 185 + ... + 5606.

It is an arithmetic number, because the mean of its divisors is an integer number (3926976).

Almost surely, 2^15699401 is an apocalyptic number.

It is an amenable number.

15699401 is a deficient number, since it is larger than the sum of its proper divisors (8503).

15699401 is an equidigital number, since it uses as much as digits as its factorization.

15699401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8502.

The product of its (nonzero) digits is 9720, while the sum is 35.

The square root of 15699401 is about 3962.2469635297. The cubic root of 15699401 is about 250.3961771763.

The spelling of 15699401 in words is "fifteen million, six hundred ninety-nine thousand, four hundred one".