7187881 has 2 divisors, whose sum is σ = 7187882. Its totient is φ = 7187880.

The previous prime is 7187861. The next prime is 7187897. The reversal of 7187881 is 1887817.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4769856 + 2418025 = 2184^2 + 1555^2 .

It is a cyclic number.

It is not a de Polignac number, because 7187881 - 2¹¹ = 7185833 is a prime.

It is a super-2 number, since 2×7187881² = 103331266540322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (7187801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3593940 + 3593941.

It is an arithmetic number, because the mean of its divisors is an integer number (3593941).

Almost surely, 2^7187881 is an apocalyptic number.

It is an amenable number.

7187881 is a deficient number, since it is larger than the sum of its proper divisors (1).

7187881 is an equidigital number, since it uses as much as digits as its factorization.

7187881 is an evil number, because the sum of its binary digits is even.

The product of its digits is 25088, while the sum is 40.

The square root of 7187881 is about 2681.0223796157. The cubic root of 7187881 is about 192.9894756537.

The spelling of 7187881 in words is "seven million, one hundred eighty-seven thousand, eight hundred eighty-one".