611764021 has 6 divisors (see below), whose sum is σ = 672434966. Its totient is φ = 556149000.

The previous prime is 611764007. The next prime is 611764039. The reversal of 611764021 is 120467116.

It can be written as a sum of positive squares in only one way, i.e., 609843025 + 1920996 = 24695^2 + 1386^2 .

It is a de Polignac number, because none of the positive numbers 2^k-611764021 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 (611764061) 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, 2527830 + ... + 2528071.

Almost surely, 2^611764021 is an apocalyptic number.

It is an amenable number.

611764021 is a deficient number, since it is larger than the sum of its proper divisors (60670945).

611764021 is a wasteful number, since it uses less digits than its factorization.

611764021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5055923 (or 5055912 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 28.

The square root of 611764021 is about 24733.8638510040. The cubic root of 611764021 is about 848.9093374663.

The spelling of 611764021 in words is "six hundred eleven million, seven hundred sixty-four thousand, twenty-one".