919913661 has 12 divisors (see below), whose sum is σ = 1346967388. Its totient is φ = 604874304.

The previous prime is 919913653. The next prime is 919913699. The reversal of 919913661 is 166319919.

It can be written as a sum of positive squares in 2 ways, for example, as 520113636 + 399800025 = 22806^2 + 19995^2 .

It is not a de Polignac number, because 919913661 - 2³ = 919913653 is a prime.

It is a super-2 number, since 2×919913661² = 1692482287388845842, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (919911661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 699430 + ... + 700743.

Almost surely, 2^919913661 is an apocalyptic number.

It is an amenable number.

919913661 is a deficient number, since it is larger than the sum of its proper divisors (427053727).

919913661 is a wasteful number, since it uses less digits than its factorization.

919913661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1400252 (or 1400249 counting only the distinct ones).

The product of its digits is 78732, while the sum is 45.

The square root of 919913661 is about 30330.0784865453. The cubic root of 919913661 is about 972.5584005038.

The spelling of 919913661 in words is "nine hundred nineteen million, nine hundred thirteen thousand, six hundred sixty-one".