1620363653 has 4 divisors (see below), whose sum is σ = 1715679180. Its totient is φ = 1525048128.

The previous prime is 1620363649. The next prime is 1620363673. The reversal of 1620363653 is 3563630261.

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

It can be written as a sum of positive squares in 2 ways, for example, as 1482019009 + 138344644 = 38497^2 + 11762^2 .

It is a cyclic number.

It is not a de Polignac number, because 1620363653 - 2² = 1620363649 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1620363673) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 47657738 + ... + 47657771.

It is an arithmetic number, because the mean of its divisors is an integer number (428919795).

Almost surely, 2^1620363653 is an apocalyptic number.

It is an amenable number.

1620363653 is a deficient number, since it is larger than the sum of its proper divisors (95315527).

1620363653 is an equidigital number, since it uses as much as digits as its factorization.

1620363653 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95315526.

The product of its (nonzero) digits is 58320, while the sum is 35.

The square root of 1620363653 is about 40253.7408572172. The cubic root of 1620363653 is about 1174.5481656130.

The spelling of 1620363653 in words is "one billion, six hundred twenty million, three hundred sixty-three thousand, six hundred fifty-three".