15987961 has 8 divisors (see below), whose sum is σ = 18043200. Its totient is φ = 14033040.

The previous prime is 15987953. The next prime is 15987977. The reversal of 15987961 is 16978951.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 15987961 - 2³ = 15987953 is a prime.

It is a super-2 number, since 2×15987961² = 511229793875042, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (15987901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24741 + ... + 25378.

It is an arithmetic number, because the mean of its divisors is an integer number (2255400).

Almost surely, 2^15987961 is an apocalyptic number.

15987961 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

15987961 is a deficient number, since it is larger than the sum of its proper divisors (2055239).

15987961 is a wasteful number, since it uses less digits than its factorization.

15987961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50159.

The product of its digits is 136080, while the sum is 46.

The square root of 15987961 is about 3998.4948418124. The cubic root of 15987961 is about 251.9209933311.

It can be divided in two parts, 1598 and 7961, that added together give a palindrome (9559).

The spelling of 15987961 in words is "fifteen million, nine hundred eighty-seven thousand, nine hundred sixty-one".