1649777420 has 24 divisors (see below), whose sum is σ = 3465599424. Its totient is φ = 659707776.

The previous prime is 1649777413. The next prime is 1649777447. The reversal of 1649777420 is 247779461.

It is a happy number.

It is a Smith number, since the sum of its digits (47) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 65672 + ... + 87248.

It is an arithmetic number, because the mean of its divisors is an integer number (144399976).

Almost surely, 2^1649777420 is an apocalyptic number.

1649777420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1649777420 is an abundant number, since it is smaller than the sum of its proper divisors (1815822004).

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

1649777420 is a wasteful number, since it uses less digits than its factorization.

1649777420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25409 (or 25407 counting only the distinct ones).

The product of its (nonzero) digits is 592704, while the sum is 47.

The square root of 1649777420 is about 40617.4521603707. The cubic root of 1649777420 is about 1181.6126137018.

The spelling of 1649777420 in words is "one billion, six hundred forty-nine million, seven hundred seventy-seven thousand, four hundred twenty".