15997970 has 16 divisors (see below), whose sum is σ = 28880280. Its totient is φ = 6380544.

The previous prime is 15997957. The next prime is 15997973. The reversal of 15997970 is 7979951.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 15531481 + 466489 = 3941^2 + 683^2 .

It is not an unprimeable number, because it can be changed into a prime (15997973) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1586 + ... + 5874.

Almost surely, 2^15997970 is an apocalyptic number.

15997970 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

15997970 is a deficient number, since it is larger than the sum of its proper divisors (12882310).

15997970 is a wasteful number, since it uses less digits than its factorization.

15997970 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4669.

The product of its (nonzero) digits is 178605, while the sum is 47.

The square root of 15997970 is about 3999.7462419509. The cubic root of 15997970 is about 251.9735526960.

The spelling of 15997970 in words is "fifteen million, nine hundred ninety-seven thousand, nine hundred seventy".