7820138 has 8 divisors (see below), whose sum is σ = 12240288. Its totient is φ = 3740044.

The previous prime is 7820123. The next prime is 7820143. The reversal of 7820138 is 8310287.

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

It is a super-2 number, since 2×7820138² = 122309116678088, which contains 22 as substring.

It is an Ulam number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 7820138.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 84956 + ... + 85047.

It is an arithmetic number, because the mean of its divisors is an integer number (1530036).

Almost surely, 2^7820138 is an apocalyptic number.

7820138 is a deficient number, since it is larger than the sum of its proper divisors (4420150).

7820138 is a wasteful number, since it uses less digits than its factorization.

7820138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 170028.

The product of its (nonzero) digits is 2688, while the sum is 29.

The square root of 7820138 is about 2796.4509650627. The cubic root of 7820138 is about 198.4897748034.

It can be divided in two parts, 7 and 820138, that multiplied together give a triangular number (5740966 = T₃₃₈₈).

The spelling of 7820138 in words is "seven million, eight hundred twenty thousand, one hundred thirty-eight".