1958628778 has 4 divisors (see below), whose sum is σ = 2937943170. Its totient is φ = 979314388.

The previous prime is 1958628773. The next prime is 1958628821. The reversal of 1958628778 is 8778268591.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 1955143089 + 3485689 = 44217^2 + 1867^2 .

It is not an unprimeable number, because it can be changed into a prime (1958628773) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 489657193 + ... + 489657196.

Almost surely, 2^1958628778 is an apocalyptic number.

1958628778 is a deficient number, since it is larger than the sum of its proper divisors (979314392).

1958628778 is an equidigital number, since it uses as much as digits as its factorization.

1958628778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 979314391.

The product of its digits is 13547520, while the sum is 61.

The square root of 1958628778 is about 44256.3981589103. The cubic root of 1958628778 is about 1251.1730381475.

The spelling of 1958628778 in words is "one billion, nine hundred fifty-eight million, six hundred twenty-eight thousand, seven hundred seventy-eight".