247981864 has 32 divisors (see below), whose sum is σ = 504080640. Its totient is φ = 113688000.

The previous prime is 247981841. The next prime is 247981879. The reversal of 247981864 is 468189742.

It is a happy number.

It is a super-2 number, since 2×247981864² = 122990009745828992, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7809 + ... + 23599.

It is an arithmetic number, because the mean of its divisors is an integer number (15752520).

Almost surely, 2^247981864 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 247981864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (252040320).

247981864 is an abundant number, since it is smaller than the sum of its proper divisors (256098776).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

247981864 is a wasteful number, since it uses less digits than its factorization.

247981864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15961 (or 15957 counting only the distinct ones).

The product of its digits is 774144, while the sum is 49.

The square root of 247981864 is about 15747.4399189202. The cubic root of 247981864 is about 628.2608150298.

It can be divided in two parts, 24798 and 1864, that added together give a palindrome (26662).

The spelling of 247981864 in words is "two hundred forty-seven million, nine hundred eighty-one thousand, eight hundred sixty-four".