51761421 has 12 divisors (see below), whose sum is σ = 75607740. Its totient is φ = 34119360.

The previous prime is 51761419. The next prime is 51761459. The reversal of 51761421 is 12416715.

It is a happy number.

51761421 is a `hidden beast` number, since 517 + 6 + 142 + 1 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 3944196 + 47817225 = 1986^2 + 6915^2 .

It is not a de Polignac number, because 51761421 - 2¹ = 51761419 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51761401) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 31510 + ... + 33111.

It is an arithmetic number, because the mean of its divisors is an integer number (6300645).

Almost surely, 2^51761421 is an apocalyptic number.

It is an amenable number.

51761421 is a deficient number, since it is larger than the sum of its proper divisors (23846319).

51761421 is a wasteful number, since it uses less digits than its factorization.

51761421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64716 (or 64713 counting only the distinct ones).

The product of its digits is 1680, while the sum is 27.

The square root of 51761421 is about 7194.5410555504. The cubic root of 51761421 is about 372.6794078946.

The spelling of 51761421 in words is "fifty-one million, seven hundred sixty-one thousand, four hundred twenty-one".