61451405 has 4 divisors (see below), whose sum is σ = 73741692. Its totient is φ = 49161120.

The previous prime is 61451387. The next prime is 61451407. The reversal of 61451405 is 50415416.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 21141604 + 40309801 = 4598^2 + 6349^2 .

It is a de Polignac number, because none of the positive numbers 2^k-61451405 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61451407) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6145136 + ... + 6145145.

It is an arithmetic number, because the mean of its divisors is an integer number (18435423).

Almost surely, 2^61451405 is an apocalyptic number.

It is an amenable number.

61451405 is a deficient number, since it is larger than the sum of its proper divisors (12290287).

61451405 is a wasteful number, since it uses less digits than its factorization.

61451405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12290286.

The product of its (nonzero) digits is 2400, while the sum is 26.

The square root of 61451405 is about 7839.0946543590. The cubic root of 61451405 is about 394.6183463100.

The spelling of 61451405 in words is "sixty-one million, four hundred fifty-one thousand, four hundred five".