51721701 has 16 divisors (see below), whose sum is σ = 74260800. Its totient is φ = 31900928.

The previous prime is 51721697. The next prime is 51721721. The reversal of 51721701 is 10712715.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 51721701 - 2² = 51721697 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51721721) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5586 + ... + 11603.

It is an arithmetic number, because the mean of its divisors is an integer number (4641300).

Almost surely, 2^51721701 is an apocalyptic number.

51721701 is a gapful number since it is divisible by the number (51) formed by its first and last digit.

It is an amenable number.

51721701 is a deficient number, since it is larger than the sum of its proper divisors (22539099).

51721701 is a wasteful number, since it uses less digits than its factorization.

51721701 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17268.

The product of its (nonzero) digits is 490, while the sum is 24.

The square root of 51721701 is about 7191.7800995303. The cubic root of 51721701 is about 372.5840562227.

The spelling of 51721701 in words is "fifty-one million, seven hundred twenty-one thousand, seven hundred one".