399501497 has 4 divisors (see below), whose sum is σ = 400508196. Its totient is φ = 398494800.

The previous prime is 399501481. The next prime is 399501523. The reversal of 399501497 is 794105993.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 794105993 = 191 ⋅4157623.

It can be written as a sum of positive squares in 2 ways, for example, as 278589481 + 120912016 = 16691^2 + 10996^2 .

It is a cyclic number.

It is not a de Polignac number, because 399501497 - 2⁴ = 399501481 is a prime.

It is a super-2 number, since 2×399501497² = 319202892210482018, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (399501407) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 502754 + ... + 503547.

It is an arithmetic number, because the mean of its divisors is an integer number (100127049).

Almost surely, 2^399501497 is an apocalyptic number.

It is an amenable number.

399501497 is a deficient number, since it is larger than the sum of its proper divisors (1006699).

399501497 is a wasteful number, since it uses less digits than its factorization.

399501497 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1006698.

The product of its (nonzero) digits is 306180, while the sum is 47.

The square root of 399501497 is about 19987.5335396842. The cubic root of 399501497 is about 736.5000890280.

The spelling of 399501497 in words is "three hundred ninety-nine million, five hundred one thousand, four hundred ninety-seven".