7621891 has 2 divisors, whose sum is σ = 7621892. Its totient is φ = 7621890.

The previous prime is 7621883. The next prime is 7621903. The reversal of 7621891 is 1981267.

It is a happy number.

It is a weak prime.

It is an emirp because it is prime and its reverse (1981267) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 7621891 - 2³ = 7621883 is a prime.

It is not a weakly prime, because it can be changed into another prime (7622891) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3810945 + 3810946.

It is an arithmetic number, because the mean of its divisors is an integer number (3810946).

Almost surely, 2^7621891 is an apocalyptic number.

7621891 is a deficient number, since it is larger than the sum of its proper divisors (1).

7621891 is an equidigital number, since it uses as much as digits as its factorization.

7621891 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6048, while the sum is 34.

The square root of 7621891 is about 2760.7772456321. Note that the first 3 decimals coincide. The cubic root of 7621891 is about 196.7981045464.

The spelling of 7621891 in words is "seven million, six hundred twenty-one thousand, eight hundred ninety-one".