51561370 has 32 divisors (see below), whose sum is σ = 109495296. Its totient is φ = 17107200.

The previous prime is 51561361. The next prime is 51561373. The reversal of 51561370 is 7316515.

It is not an unprimeable number, because it can be changed into a prime (51561373) 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, 9711 + ... + 14050.

It is an arithmetic number, because the mean of its divisors is an integer number (3421728).

Almost surely, 2^51561370 is an apocalyptic number.

51561370 is an abundant number, since it is smaller than the sum of its proper divisors (57933926).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

51561370 is a wasteful number, since it uses less digits than its factorization.

51561370 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23806.

The product of its (nonzero) digits is 3150, while the sum is 28.

The square root of 51561370 is about 7180.6246246410. The cubic root of 51561370 is about 372.1986692687.

Adding to 51561370 its reverse (7316515), we get a palindrome (58877885).

The spelling of 51561370 in words is "fifty-one million, five hundred sixty-one thousand, three hundred seventy".