1958778 has 12 divisors (see below), whose sum is σ = 4244058. Its totient is φ = 652920.

The previous prime is 1958777. The next prime is 1958813. The reversal of 1958778 is 8778591.

It can be written as a sum of positive squares in only one way, i.e., 1595169 + 363609 = 1263^2 + 603^2 .

It is a super-2 number, since 2×1958778² = 7673622506568, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1958773) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 54393 + ... + 54428.

2^1958778 is an apocalyptic number.

1958778 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

1958778 is an abundant number, since it is smaller than the sum of its proper divisors (2285280).

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

1958778 is a wasteful number, since it uses less digits than its factorization.

1958778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 108829 (or 108826 counting only the distinct ones).

The product of its digits is 141120, while the sum is 45.

The square root of 1958778 is about 1399.5635033824. The cubic root of 1958778 is about 125.1204811703.

The spelling of 1958778 in words is "one million, nine hundred fifty-eight thousand, seven hundred seventy-eight".