51001405 has 48 divisors (see below), whose sum is σ = 78140160. Its totient is φ = 31667328.

The previous prime is 51001381. The next prime is 51001421. The reversal of 51001405 is 50410015.

It is a happy number.

It is not a de Polignac number, because 51001405 - 2¹³ = 50993213 is a prime.

It is a super-2 number, since 2×51001405² = 5202286623948050, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 213276 + ... + 213514.

It is an arithmetic number, because the mean of its divisors is an integer number (1627920).

Almost surely, 2^51001405 is an apocalyptic number.

It is an amenable number.

51001405 is a deficient number, since it is larger than the sum of its proper divisors (27138755).

51001405 is a wasteful number, since it uses less digits than its factorization.

51001405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 338 (or 331 counting only the distinct ones).

The product of its (nonzero) digits is 100, while the sum is 16.

The square root of 51001405 is about 7141.5267975413. The cubic root of 51001405 is about 370.8463823488.

The spelling of 51001405 in words is "fifty-one million, one thousand, four hundred five".