1649613021 has 8 divisors (see below), whose sum is σ = 2513696064. Its totient is φ = 942636000.

The previous prime is 1649613011. The next prime is 1649613023. The reversal of 1649613021 is 1203169461.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1649613021 - 2⁷ = 1649612893 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1649613023) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 39276480 + ... + 39276521.

It is an arithmetic number, because the mean of its divisors is an integer number (314212008).

Almost surely, 2^1649613021 is an apocalyptic number.

It is an amenable number.

1649613021 is a deficient number, since it is larger than the sum of its proper divisors (864083043).

1649613021 is an equidigital number, since it uses as much as digits as its factorization.

1649613021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 78553011.

The product of its (nonzero) digits is 7776, while the sum is 33.

The square root of 1649613021 is about 40615.4283616460. The cubic root of 1649613021 is about 1181.5733634808.

The spelling of 1649613021 in words is "one billion, six hundred forty-nine million, six hundred thirteen thousand, twenty-one".