1616461778 has 4 divisors (see below), whose sum is σ = 2424692670. Its totient is φ = 808230888.

The previous prime is 1616461771. The next prime is 1616461783. The reversal of 1616461778 is 8771646161.

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., 1490191609 + 126270169 = 38603^2 + 11237^2 .

It is a super-2 number, since 2×1616461778² = 5225897359469842568, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1616461771) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 404115443 + ... + 404115446.

Almost surely, 2^1616461778 is an apocalyptic number.

1616461778 is a deficient number, since it is larger than the sum of its proper divisors (808230892).

1616461778 is an equidigital number, since it uses as much as digits as its factorization.

1616461778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 808230891.

The product of its digits is 338688, while the sum is 47.

The square root of 1616461778 is about 40205.2456527752. The cubic root of 1616461778 is about 1173.6046276908.

The spelling of 1616461778 in words is "one billion, six hundred sixteen million, four hundred sixty-one thousand, seven hundred seventy-eight".