6921913653 has 6 divisors (see below), whose sum is σ = 9998319734. Its totient is φ = 4614609096.

The previous prime is 6921913643. The next prime is 6921913657. The reversal of 6921913653 is 3563191296.

It can be written as a sum of positive squares in only one way, i.e., 6793386084 + 128527569 = 82422^2 + 11337^2 .

It is not a de Polignac number, because 6921913653 - 2⁴ = 6921913637 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 6921913599 and 6921913608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6921913657) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 384550750 + ... + 384550767.

Almost surely, 2^6921913653 is an apocalyptic number.

It is an amenable number.

6921913653 is a deficient number, since it is larger than the sum of its proper divisors (3076406081).

6921913653 is a wasteful number, since it uses less digits than its factorization.

6921913653 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 769101523 (or 769101520 counting only the distinct ones).

The product of its digits is 262440, while the sum is 45.

The square root of 6921913653 is about 83198.0387569322. The cubic root of 6921913653 is about 1905.7915300430.

The spelling of 6921913653 in words is "six billion, nine hundred twenty-one million, nine hundred thirteen thousand, six hundred fifty-three".