5401854507721 has 27 divisors (see below), whose sum is σ = 6675509648007. Its totient is φ = 4357575472320.

The previous prime is 5401854507671. The next prime is 5401854507767. The reversal of 5401854507721 is 1277054581045.

The square root of 5401854507721 is 2324189.

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

It can be written as a sum of positive squares in only one way, i.e., 4205596070025 + 1196258437696 = 2050755^2 + 1093736^2 .

It is not a de Polignac number, because 5401854507721 - 2⁷ = 5401854507593 is a prime.

It is a super-2 number, since 2×5401854507721² (a number of 26 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (49).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (5401854507121) 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, 276568726 + ... + 276588256.

Almost surely, 2^{5401854507721} is an apocalyptic number.

5401854507721 is the 2324189-th square number.

5401854507721 is the 1162095-th centered octagonal number.

It is an amenable number.

5401854507721 is a deficient number, since it is larger than the sum of its proper divisors (1273655140286).

5401854507721 is an frugal number, since it uses more digits than its factorization.

5401854507721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39110 (or 19555 counting only the distinct ones).

The product of its (nonzero) digits is 1568000, while the sum is 49.

Multiplying 5401854507721 by its sum of digits (49), we get a square (264690870878329 = 16269323²).

5401854507721 divided by its sum of digits (49) gives a square (110241928729 = 332027²).

The spelling of 5401854507721 in words is "five trillion, four hundred one billion, eight hundred fifty-four million, five hundred seven thousand, seven hundred twenty-one".