1974977704921 has 27 divisors (see below), whose sum is σ = 2272141722621. Its totient is φ = 1715547909504.

The previous prime is 1974977704919. The next prime is 1974977704927. The reversal of 1974977704921 is 1294077794791.

The square root of 1974977704921 is 1405339.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 17832664521 + 1957145040400 = 133539^2 + 1398980^2 .

It is not a de Polignac number, because 1974977704921 - 2¹ = 1974977704919 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1974977704927) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 310576740 + ... + 310583098.

Almost surely, 2^{1974977704921} is an apocalyptic number.

1974977704921 is the 1405339-th square number.

1974977704921 is the 702670-th centered octagonal number.

It is an amenable number.

1974977704921 is a deficient number, since it is larger than the sum of its proper divisors (297164017700).

1974977704921 is an frugal number, since it uses more digits than its factorization.

1974977704921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12778 (or 6389 counting only the distinct ones).

The product of its (nonzero) digits is 56010528, while the sum is 67.

The spelling of 1974977704921 in words is "one trillion, nine hundred seventy-four billion, nine hundred seventy-seven million, seven hundred four thousand, nine hundred twenty-one".