15401997 has 12 divisors (see below), whose sum is σ = 23958844. Its totient is φ = 9478080.

The previous prime is 15401993. The next prime is 15402001. The reversal of 15401997 is 79910451.

It is an interprime number because it is at equal distance from previous prime (15401993) and next prime (15402001).

It can be written as a sum of positive squares in 2 ways, for example, as 3437316 + 11964681 = 1854^2 + 3459^2 .

It is not a de Polignac number, because 15401997 - 2² = 15401993 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15401993) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 65704 + ... + 65937.

Almost surely, 2^15401997 is an apocalyptic number.

It is an amenable number.

15401997 is a deficient number, since it is larger than the sum of its proper divisors (8556847).

15401997 is a wasteful number, since it uses less digits than its factorization.

15401997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 131660 (or 131657 counting only the distinct ones).

The product of its (nonzero) digits is 11340, while the sum is 36.

The square root of 15401997 is about 3924.5378071819. The cubic root of 15401997 is about 248.8049471640.

The spelling of 15401997 in words is "fifteen million, four hundred one thousand, nine hundred ninety-seven".